Antifungal compound process

ABSTRACT

The present invention relates to a process for preparing compound 1 that is useful as an antifungal agent. In particular, the invention seeks to provide new methodology for preparing compound 1 and substituted derivatives thereof.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Patent Application Ser. No. 61/955,650 filed Mar. 19, 2014, which is expressly incorporated by reference herein.

The present invention relates to a process for preparing compound 1 that is useful as an antifungal agent. In particular, the invention seeks to provide a new methodology for preparing compound 1 and substituted derivatives thereof.

STATEMENT OF GOVERNMENT SUPPORT

This invention was created in the performance of a Cooperative Research and Development Agreement with the National Institutes of Health, an Agency of the Department of Health and Human Services. The Government of the United States has certain rights in this invention.

BACKGROUND

Living organisms have developed tightly regulated processes that specifically import metals, transport them to intracellular storage sites and ultimately transport them to sites of use. One of the most important functions of metals such as zinc and iron in biological systems is to enable the activity of metalloenzymes. Metalloenzymes are enzymes that incorporate metal ions into the enzyme active site and utilize the metal as a part of the catalytic process. More than one-third of all characterized enzymes are metalloenzymes.

The function of metalloenzymes is highly dependent on the presence of the metal ion in the active site of the enzyme. It is well recognized that agents which bind to and inactivate the active site metal ion dramatically decrease the activity of the enzyme. Nature employs this same strategy to decrease the activity of certain metalloenzymes during periods in which the enzymatic activity is undesirable. For example, the protein TIMP (tissue inhibitor of metalloproteases) binds to the zinc ion in the active site of various matrix metalloprotease enzymes and thereby arrests the enzymatic activity. The pharmaceutical industry has used the same strategy in the design of therapeutic agents. For example, the azole antifungal agents fluconazole and voriconazole contain a 1-(1,2,4-triazole) group that binds to the heme iron present in the active site of the target enzyme lanosterol demethylase and thereby inactivates the enzyme.

In the design of clinically safe and effective metalloenzyme inhibitors, use of the most appropriate metal-binding group for the particular target and clinical indication is critical. If a weakly binding metal-binding group is utilized, potency may be suboptimal. On the other hand, if a very tightly binding metal-binding group is utilized, selectivity for the target enzyme versus related metalloenzymes may be suboptimal. The lack of optimal selectivity can be a cause for clinical toxicity due to unintended inhibition of these off-target metalloenzymes. One example of such clinical toxicity is the unintended inhibition of human drug metabolizing enzymes such as CYP2C9, CYP2C19 and CYP3A4 by the currently-available azole antifungal agents such as fluconazole and voriconazole. It is believed that this off-target inhibition is caused primarily by the indiscriminate binding of the currently utilized 1-(1,2,4-triazole) to iron in the active site of CYP2C9, CYP2C19 and CYP3A4. Another example of this is the joint pain that has been observed in many clinical trials of matrix metalloproteinase inhibitors. This toxicity is considered to be related to inhibition of off-target metalloenzymes due to indiscriminate binding of the hydroxamic acid group to zinc in the off-target active sites.

Therefore, the search for metal-binding groups that can achieve a better balance of potency and selectivity remains an important goal and would be significant in the realization of therapeutic agents and methods to address currently unmet needs in treating and preventing diseases, disorders and symptoms thereof. Similarly, methods of synthesizing such therapeutic agents on the laboratory and, ultimately, commercial scale is needed. Addition of metal-based nucleophiles (Zn, Zr, Ce, Ti, Mg, Mn, Li) to azole-methyl substituted ketones have been effected in the synthesis of voriconazole (M. Butters, Org. Process Res. Dev. 2001, 5, 28-36). The nucleophile in these examples was an ethyl-pyrimidine substrate. Similarly, optically active azole-methyl epoxide has been prepared as precursor electrophile toward the synthesis of ravuconazole (A. Tsuruoka, Chem. Pharm. Bull. 1998, 46, 623-630). Despite this, the development of methodology with improved efficiency and selectivity is desirable.

BRIEF SUMMARY OF THE INVENTION

The invention is directed toward methods of synthesis of 1 or 1a. The methods can comprise the compounds herein. A first aspect of the invention relates to a process for preparing a compound of formula 1, or a pharmaceutically acceptable salt, hydrate, solvate, complex or prodrug thereof.

The compounds herein include those wherein the compound is identified as attaining affinity, at least in part, for a metalloenzyme by formation of one or more of the following types of chemical interactions or bonds to a metal: sigma bonds, covalent bonds, coordinate-covalent bonds, ionic bonds, pi bonds, delta bonds, or backbonding interactions.

Methods for assessing metal-ligand binding interactions are known in the art as exemplified in references including, for example, “Principles of Bioinorganic Chemistry” by Lippard and Berg, University Science Books, (1994); “Mechanisms of Inorganic Reactions” by Basolo and Pearson John Wiley & Sons Inc; 2nd edition (September 1967); “Biological Inorganic Chemistry” by Ivano Bertini, Harry Gray, Ed Stiefel, Joan Valentine, University Science Books (2007); Xue et al. “Nature Chemical Biology”, vol. 4, no. 2, 107-109 (2008).

In the following aspects, reference is made to the schemes and compounds herein, including the reagents and reaction conditions delineated herein. Other aspects include any of the compounds, reagents, transformations or methods thereof delineated in the examples herein (in whole or in part), including as embodiments with single elements (e.g., compounds or transformations) or embodiments including multiple elements (e.g., compounds or transformations).

In one aspect, the invention provides a process to prepare a compound of formula II:

comprising epoxide opening of a compound of formula I:

to provide a compound of formula II; wherein R is

In another aspect, the invention provides a process to prepare amino-alcohol 1-6 or 1-7, or a mixture thereof:

comprising arylation of substituted pyridine 4b or 4c, or a mixture thereof:

to provide compound 1-6 or 1-7, or a mixture thereof;

wherein each R₁ is independently halo, —O(C═O)-alkyl, —O(C═O)-substituted alkyl, —O(C═O)-aryl, —O(C═O)-substituted aryl, —O(C═O)—O-alkyl, —O(C═O)—O-substituted alkyl, —O(C═O)—O-aryl, —O(C═O)—O-substituted aryl, —O(SO₂)-alkyl, —O(SO₂)-substituted alkyl, —O(SO₂)-aryl, or —O(SO₂)-substituted aryl.

In one embodiment, the invention provides a process to prepare a compound of formula IV:

comprising olefination of a compound of formula III:

to provide a compound of formula IV; wherein R is

In another embodiment, the invention provides a process to prepare a compound of formula V or Va, or a mixture thereof:

comprising dihydroxylation of a compound of formula IV:

to provide a compound of formula V or Va. or a mixture thereof; wherein R is

In another embodiment, the invention provides a process to prepare a compound of formula VI or VIa, or a mixture thereof:

comprising activation of the primary alcohol of a compound of formula V or Va, or a mixture thereof:

to a provide a compound of formula VI or VIa, or a mixture thereof;

wherein R is

and

each Y is independently —OSO₂-alkyl, —OSO₂-substituted alkyl, —OSO₂-aryl, —OSO₂-substituted aryl, —O(C═O)-alkyl, —O(C═O)-substituted alkyl, —O(C═O)-aryl, —O(C═O)-substituted aryl, or halogen.

In another embodiment, the invention provides a process to prepare a compound of formula VII or VIIa, or a mixture thereof:

comprising ring closure of a compound of formula VI or VIa, or a mixture thereof:

to provide a compound of formula VII or VIIa, or a mixture thereof;

wherein R is

and

each Y is independently —OSO₂-alkyl, —OSO₂-substituted alkyl, —OSO₂-aryl, —OSO₂-substituted aryl, —O(C═O)-alkyl, —O(C═O)-substituted alkyl, —O(C═O)-aryl, —O(C═O)-substituted aryl, or halogen.

In another embodiment, the invention provides a process of enriching the enantiomeric purity of an enantiomeric compound mixture, comprising:

(i) crystallizing said enantiomeric compound mixture with a chiral acid in a suitable solvent or solvent mixture, wherein:

-   -   the suitable solvent or solvent mixture is selected from         acetonitrile, isopropanol, ethanol, water, methanol, or         combinations thereof; and     -   the enantiomeric compound mixture comprises

and

(ii) isolating the enantio-enriched compound mixture

(iii) reslurrying the enantio-enriched chiral salt mixture in a slurrying solvent or slurrying solvent mixture; and

(iv) free-basing the enantio-enriched chiral salt mixture to provide the enantio-enriched compound mixture.

In another embodiment, the invention provides a process of enriching the enantiomeric purity of an enantiomeric compound mixture, comprising:

(i) crystallizing said enantiomeric compound mixture with a chiral acid in a suitable solvent or solvent mixture, wherein:

-   -   the suitable solvent or solvent mixture is selected from         acetonitrile, isopropanol, ethanol, water, methanol, or         combinations thereof; and     -   the enantiomeric compound mixture comprises

and

(ii) isolating the enantio-enriched compound mixture; and

(iii) free-basing the enantio-enriched chiral salt mixture to provide the enantio-enriched compound mixture.

In another aspect, the chiral acid from any embodiment presented herein is selected from the group consisting of tartaric acid, di-benzoyltartaric acid, malic acid, camphoric acid, camphorsulfonic acid, ascorbic acid, and di-p-toluoyltartaric acid;

In another aspect, the suitable solvent or solvent mixture from any embodiments presented herein is 1-propanol, 1-butanol, ethyl acetate, tetrahydrofuran, 2-methyltetrahydrofuran, toluene, methyl tert-butylether, diethyl ether, dichloromethane, 1,4-dioxane, 1,2-dimethoxyethane, isopropyl acetate, heptane, hexane, cyclohexane, or octane, or combinations thereof.

In another aspect, the slurrying solvent solvent or slurrying solvent mixture from any embodiments presented herein is 1-propanol, 1-butanol, ethyl acetate, tetrahydrofuran, 2-methyltetrahydrofuran, toluene, methyl tert-butylether, diethyl ether, dichloromethane, 1,4-dioxane, 1,2-dimethoxyethane, isopropyl acetate, heptane, hexane, cyclohexane, or octane, or combinations thereof.

In another aspect, the suitable solvent or solvent mixture from any embodiments presented herein is a) acetonitrile or b) a mixture of acetonitrile and isopropanol. Alternatively, another aspect is where the mixture of acetonitrile and methanol comprises 80-90% acetonitrile and 10-20% isopropanol.

In another aspect, the slurrying solvent or slurrying solvent mixture from any embodiments presented herein is a) acetonitrile or b) a mixture of acetonitrile and isopropanol. Alternatively, another aspect is where the mixture of acetonitrile and isopropanol comprises 80-90% acetonitrile and 10-20% isopropanol.

In another aspect, the invention provides a process to prepare compound 1 or 1a, or a mixture thereof:

comprising converting amide 2c:

to compound 1 or 1a, or mixtures thereof;

wherein R₁ is halo, —O(C═O)-alkyl, —O(C═O)-substituted alkyl, —O(C═O)-aryl, —O(C═O)-substituted aryl, —O(C═O)—O-alkyl, —O(C═O)—O-substituted alkyl, —O(C═O)—O-aryl, —O(C═O)—O-substituted aryl, —O(SO₂)-alkyl, —O(SO₂)-substituted alkyl, —O(SO₂)-aryl, or —O(SO₂)-substituted aryl;

A is N(OMe)Me, NR₈R₉, or

p is 1, 2, 3, or 4;

q is 1, 2, 3, or 4;

each R₈ and R₉ are each independently H, alkyl, substituted alkyl, aryl, substituted aryl, heteroaryl, or substituted heteroaryl.

In another aspect, the invention provides a process to prepare compound 1 or 1a, or a mixture thereof:

comprising converting amide 2c:

to compound 1 or 1a, or mixtures thereof;

wherein R₁ is halo, —O(C═O)-alkyl, —O(C═O)-substituted alkyl, —O(C═O)-aryl, —O(C═O)-substituted aryl, —O(C═O)—O-alkyl, —O(C═O)—O-substituted alkyl, —O(C═O)—O-aryl, —O(C═O)—O-substituted aryl, —O(SO₂)-alkyl, —O(SO₂)-substituted alkyl, —O(SO₂)-aryl, or —O(SO₂)-substituted aryl;

B is N(OMe)Me, NR₈R₉, or

X is O, NR₈, or S;

r is 2, 3, or 4;

s is 2, 3, or 4;

each R₈ and R₉ are each independently H, alkyl, substituted alkyl, aryl, substituted aryl, heteroaryl, or substituted heteroaryl.

In another aspect, the invention provides a process to prepare compound 1 or 1a, or a mixture thereof:

comprising converting morpholine amide 2b:

to compound 1 or 1a, or mixtures thereof;

wherein R₁ is halo, —O(C═O)-alkyl, —O(C═O)-substituted alkyl, —O(C═O)-aryl, —O(C═O)-substituted aryl, —O(C═O)—O-alkyl, —O(C═O)—O-substituted alkyl, —O(C═O)—O-aryl, —O(C═O)—O-substituted aryl, —O(SO₂)-alkyl, —O(SO₂)-substituted alkyl, —O(SO₂)-aryl, or —O(SO₂)-substituted aryl.

In another aspect, the invention provides a process comprising reacting morpholine amide 2b:

wherein M is Mg or MgX; and X is halogen; to provide compound 1 or 1a, or a mixture thereof:

wherein R₁ is halo, —O(C═O)-alkyl, —O(C═O)-substituted alkyl, —O(C═O)-aryl, —O(C═O)-substituted aryl, —O(C═O)—O-alkyl, —O(C═O)—O-substituted alkyl, —O(C═O)—O-aryl, —O(C═O)—O-substituted aryl, —O(SO₂)-alkyl, —O(SO₂)-substituted alkyl, —O(SO₂)-aryl, or —O(SO₂)-substituted aryl.

In another aspect, the invention provides a process comprising reacting morpholine amide 2b:

wherein M is Mg or MgX, Li, AlX₂; and X is halogen, alkyl, or aryl; to provide compound 1 or 1a, or a mixture thereof:

wherein R₁ is halo, —O(C═O)-alkyl, —O(C═O)-substituted alkyl, —O(C═O)-aryl, —O(C═O)-substituted aryl, —O(C═O)—O-alkyl, —O(C═O)—O-substituted alkyl, —O(C═O)—O-aryl, —O(C═O)—O-substituted aryl, —O(SO₂)-alkyl, —O(SO₂)-substituted alkyl, —O(SO₂)-aryl, or —O(SO₂)-substituted aryl.

In another aspect, any of the embodiments presented herein may comprise amidation of ester 2:

to provide morpholine amide 2b:

wherein each R₁ is independently halo, —O(C═O)-alkyl, —O(C═O)-substituted alkyl, —O(C═O)-aryl, —O(C═O)-substituted aryl, —O(C═O)—O-alkyl, —O(C═O)—O-substituted alkyl, —O(C═O)—O-aryl, —O(C═O)—O-substituted aryl, —O(SO₂)-alkyl, —O(SO₂)-substituted alkyl, —O(SO₂)-aryl, or —O(SO₂)-substituted aryl.

In another aspect, any of the embodiments presented herein may comprise amidation of ester 2d:

to provide morpholine amide 2b:

wherein each R₁ is independently halo, —O(C═O)-alkyl, —O(C═O)-substituted alkyl, —O(C═O)-aryl, —O(C═O)-substituted aryl, —O(C═O)—O-alkyl, —O(C═O)—O-substituted alkyl, —O(C═O)—O-aryl, —O(C═O)—O-substituted aryl, —O(SO₂)-alkyl, —O(SO₂)-substituted alkyl, —O(SO₂)-aryl, or —O(SO₂)-substituted aryl; and

R₈ is H, alkyl, substituted alkyl, aryl, substituted aryl, heteroaryl, or substituted heteroaryl.

In another aspect, any of the embodiments presented herein may comprise reacting ester 2:

with morpholine to provide morpholine amide 2b:

wherein each R₁ is independently halo, —O(C═O)-alkyl, —O(C═O)-substituted alkyl, —O(C═O)-aryl, —O(C═O)-substituted aryl, —O(C═O)—O-alkyl, —O(C═O)—O-substituted alkyl, —O(C═O)—O-aryl, —O(C═O)—O-substituted aryl, —O(SO₂)-alkyl, —O(SO₂)-substituted alkyl, —O(SO₂)-aryl, or —O(SO₂)-substituted aryl.

In another aspect, the invention provides a process to prepare compound 1 or 1a, or a mixture thereof:

comprising epoxide-opening of a compound of formula I, VII or VIIa:

to provide a compound of formula II, VIII or VIIIa:

wherein each R₂ is independently

halo, —O(C═O)-alkyl, —O(C═O)-substituted alkyl, —O(C═O)-aryl, —O(C═O)-substituted aryl, —O(C═O)—O-alkyl, —O(C═O)—O-substituted alkyl, —O(C═O)—O-aryl, —O(C═O)—O-substituted aryl, —O(SO₂)-alkyl, —O(SO₂)-substituted alkyl, —O(SO₂)-aryl, or —O(SO₂)-substituted aryl.

In another aspect, the invention provides a process to prepare compound 1 or 1a, or mixtures thereof:

comprising forming the tetrazole of substituted-pyridine 4d or 4e, or a mixture thereof:

to tetrazole 6c or 6d,

or a mixture thereof; wherein each R₂ is independently

halo, —O(C═O)-alkyl, —O(C═O)-substituted alkyl, —O(C═O)-aryl, —O(C═O)-substituted aryl, —O(C═O)—O-alkyl, —O(C═O)—O-substituted alkyl, —O(C═O)—O-aryl, —O(C═O)—O-substituted aryl, —O(SO₂)-alkyl, —O(SO₂)-substituted alkyl, —O(SO₂)-aryl, or —O(SO₂)-substituted aryl.

In another aspect, the invention provides a process to prepare compound 1 or 1a, or a mixture thereof:

comprising the arylation of amino-alcohol 4b or 4c,

or

or a mixture thereof, to amino aryl-pyridine 1-6* or 1-7*,

or

or a mixture thereof;

wherein each R₁ is independently halo, —O(C═O)-alkyl, —O(C═O)-substituted alkyl, —O(C═O)-aryl, —O(C═O)-substituted aryl, —O(C═O)—O-alkyl, —O(C═O)—O-substituted alkyl, —O(C═O)—O-aryl, —O(C═O)—O-substituted aryl, —O(SO₂)-alkyl, —O(SO₂)-substituted alkyl, —O(SO₂)-aryl, or —O(SO₂)-substituted aryl.

In another aspect, the invention provides a process to prepare compound 1 or 1a, or a mixture thereof:

comprising converting a compound of formula Vb or Vc, or a mixture thereof:

to compound 1 or 1a, or a mixture thereof;

wherein each R₂ is independently

halo, —O(C═O)-alkyl, —O(C═O)-substituted alkyl, —O(C═O)-aryl, —O(C═O)-substituted aryl, —O(C═O)—O-alkyl, —O(C═O)—O-substituted alkyl, —O(C═O)—O-aryl, —O(C═O)—O-substituted aryl, —O(SO₂)-alkyl, —O(SO₂)-substituted alkyl, —O(SO₂)-aryl, or —O(SO₂)-substituted aryl.

In another aspect, the invention provides a process to prepare compound 1 or 1a, or a mixture thereof:

comprising converting a compound of formula 15:

to compound 1 or 1a;

wherein R₁ is halo, —O(C═O)-alkyl, —O(C═O)-substituted alkyl, —O(C═O)-aryl, —O(C═O)-substituted aryl, —O(C═O)—O-alkyl, —O(C═O)—O-substituted alkyl, —O(C═O)—O-aryl, —O(C═O)—O-substituted aryl, —O(SO₂)-alkyl, —O(SO₂)-substituted alkyl, —O(SO₂)-aryl, or —O(SO₂)-substituted aryl.

In another aspect, any of the embodiments presented herein may comprise reacting a compound of formula IVa:

under asymmetric dihydroxylation conditions to provide a compound of formula Vb or Vc, or mixtures thereof:

wherein the asymmetric dihydroxylation conditions comprise:

(i) AD-mix alpha or AD-mix beta; or

(ii) a first oxidant in catalytic amount, a second oxidant in stoichiometric amount, a base, and a chiral ligand; and

wherein each R₂ is independently

halo, —O(C═O)-alkyl, —O(C═O)-substituted alkyl, —O(C═O)-aryl, —O(C═O)-substituted aryl, —O(C═O)—O-alkyl, —O(C═O)—O-substituted alkyl, —O(C═O)—O-aryl, —O(C═O)—O-substituted aryl, —O(SO₂)-alkyl, —O(SO₂)-substituted alkyl, —O(SO₂)-aryl, or —O(SO₂)-substituted aryl.

In another aspect, any of the embodiments presented herein may comprise a process, wherein:

(i) the first oxidant in catalytic amount is Osa_(t) or K₂OsO₂(OH)₄;

(ii) the second oxidant in stoichiometric amount is K₃Fe(CN)₆ or N-methylmorpholine-N-oxide;

(iii) the base is Cs₂CO₃, Na₂CO₃, K₂CO₃ or NaHCO₃; and

(iv) the chiral ligand is selected from the group consisting of (DHQ)₂PHAL, (DHQD)₂PHAL, (DHQD)₂AQN, (DHQ)₂AQN, (DHQD)₂PYR, and (DHQ)₂PYR.

In another aspect, any of the embodiments presented herein may comprise a process, wherein the chiral ligand is selected from the group consisting of (DHQ)₂PHAL, (DHQD)₂PHAL, (DHQD)₂AQN, and (DHQD)₂PYR.

In another aspect, any of the embodiments presented herein may comprise the addition of MeSO₂NH₂.

In another aspect, any of the embodiments presented herein may comprise a process comprising converting a compound of formula VIb or VIc, or a mixture thereof:

to a compound of formula VII or VIIa, or a mixture thereof:

wherein each R₂ is independently

halo, —O(C═O)-alkyl, —O(C═O)-substituted alkyl, —O(C═O)-aryl, —O(C═O)-substituted aryl, —O(C═O)—O-alkyl, —O(C═O)—O-substituted alkyl, —O(C═O)—O-aryl, —O(C═O)—O-substituted aryl, —O(SO₂)-alkyl, —O(SO₂)-substituted alkyl, —O(SO₂)-aryl, or —O(SO₂)-substituted aryl; and Y is —OSO₂-alkyl, —OSO₂-substituted alkyl, —OSO₂-aryl, —OSO₂-substituted aryl, —O(C═O)-alkyl, —O(C═O)-substituted alkyl, —O(C═O)-aryl, —O(C═O)-substituted aryl, or halogen.

In another aspect, any of the embodiments presented herein may comprise a process comprising:

(i) activating the primary alcohol of 2-6a or 2-6c,

or a mixture thereof, to provide a compound of formula 2-7a or 2-7c,

or a mixture thereof;

wherein Y is —OSO₂-alkyl, —OSO₂-substituted alkyl, —OSO₂-aryl, —OSO₂-substituted aryl, —O(C═O)-alkyl, —O(C═O)-substituted alkyl, —O(C═O)-aryl, —O(C═O)-substituted aryl, or halogen;

(ii) ring-closing of a compound of 2-7a or 2-7c,

or a mixture thereof, to provide epoxide 5* or 5b*,

or a mixture thereof;

(iii) ring-opening epoxide 5* or 5b*,

or a mixture thereof, to provide amino-alcohol 1-6* or 1-7*,

or a mixture thereof; and

(iv) forming the tetrazole of amino-alcohol 1-6* or 1-7*,

to provide compound 1 or 1a,

or a mixture thereof.

In another aspect, any of the embodiments presented herein may comprise a process comprising:

(i) activating the primary alcohol 2-6b or 2-6d,

or a mixture thereof, to provide a compound of formula 2-7b or 2-7d,

or a mixture thereof;

wherein each Y is independently —OSO₂-alkyl, —OSO₂-substituted alkyl, —OSO₂-aryl, —OSO₂-substituted aryl, —O(C═O)-alkyl, —O(C═O)-substituted alkyl, —O(C═O)-aryl, —O(C═O)-substituted aryl, or halogen;

(ii) ring-closing of compound 2-7b or 2-7d,

or a mixture thereof, to provide epoxide 4* or 4c*,

or a mixture thereof;

(iii) ring-opening epoxide 4* or 4c*,

or a mixture thereof, to provide amino-alcohol 4b or 4c,

or a mixture thereof;

(iv) arylating amino-alcohol 4b or 4c,

or a mixture thereof, to provide aryl-pyridine 1-6* or 1-7*,

or a mixture thereof; and

(v) forming the tetrazole of amino-alcohol 1-6* or 1-7*,

or a mixture thereof, to provide compound 1 or 1a,

or a mixture thereof;

wherein each R₁ is independently halo, —O(C═O)-alkyl, —O(C═O)-substituted alkyl, —O(C═O)-aryl, —O(C═O)-substituted aryl, —O(C═O)—O-alkyl, —O(C═O)—O-substituted alkyl, —O(C═O)—O-aryl, —O(C═O)—O-substituted aryl, —O(SO₂)-alkyl, —O(SO₂)-substituted alkyl, —O(SO₂)-aryl, or —O(SO₂)-substituted aryl.

In another aspect, the invention provides a compound of formula IVb:

wherein R is

and

each R₁₂ is independently H, optionally substituted alkyl, optionally substituted alkenyl, optionally substituted aryl, optionally substituted heteroaryl, optionally substituted cycloalkyl, or optionally substituted hetrocyclyl.

In another aspect, the invention provides a compound of formula VI* or VIa*, or a mixture thereof:

wherein R is

each Y₁ is independently OH, —OSO₂-alkyl, —OSO₂-substituted alkyl, —OSO₂-aryl, —OSO₂-substituted aryl, —O(C═O)-alkyl, —O(C═O)-substituted alkyl, —O(C═O)-aryl, —O(C═O)-substituted aryl, or halogen; and

each R₁₂ is independently H, optionally substituted alkyl, optionally substituted alkenyl, optionally substituted aryl, optionally substituted heteroaryl, optionally substituted cycloalkyl, or optionally substituted heterocyclyl.

In another aspect, the invention provides a process to prepare a compound of formula IX or IXa, or a mixture thereof, comprising:

(i) combining compound 1 or 1a,

or a mixture thereof, a sulfonic acid

and a crystallization solvent or crystallization solvent mixture;

(ii) diluting the mixture from step (i) with a crystallization co-solvent or crystallization co-solvent mixture; and

(iii) isolating a compound of formula IX or IXa, or a mixture thereof;

wherein each Z is independently aryl, substituted aryl, alkyl, or substituted alkyl.

In another aspect, the invention provides a process to prepare a compound of formula 5* or 5b*,

or a mixture thereof, the method comprising converting a compound of formula IVa,

wherein R₂ is

halo, —O(C═O)-alkyl, —O(C═O)-substituted alkyl, —O(C═O)-aryl, —O(C═O)-substituted aryl, —O(C═O)—O-alkyl, —O(C═O)—O-substituted alkyl, —O(C═O)—O-aryl, —O(C═O)—O-substituted aryl, —O(SO₂)-alkyl, —O(SO₂)-substituted alkyl, —O(SO₂)-aryl, or —O(SO₂)-substituted aryl.

In another aspect, any of the embodiments presented herein may comprise reacting a compound of formula IVa:

under asymmetric dihydroxylation conditions to provide a compound of formula Vb or Vc, or mixtures thereof:

wherein the asymmetric dihydroxylation conditions comprise:

(i) AD-mix alpha or AD-mix beta; or

(ii) a first oxidant in catalytic amount, a second oxidant in stoichiometric amount, a base, and a chiral ligand; and

wherein each R₂ is independently halo, —O(C═O)-alkyl, —O(C═O)-substituted alkyl, —O(C═O)-aryl, —O(C═O)-substituted aryl, —O(C═O)-O-alkyl, —O(C═O)—O-substituted alkyl, —O(C═O)—O-aryl, —O(C═O)-O-substituted aryl, —O(SO₂)-alkyl, —O(SO₂)-substituted alkyl, —O(SO₂)-aryl, or —O(SO₂)-substituted aryl.

In another aspect, any of the embodiments presented herein may comprise converting a compound of formula Vb or Vc, or a mixture thereof:

to provide a compound of formula of 5* or 5b*,

or a mixture thereof:

wherein each R₂ is independently

halo, —O(C═O)-alkyl, —O(C═O)-substituted alkyl, —O(C═O)-aryl, —O(C═O)-substituted aryl, —O(C═O)—O-alkyl, —O(C═O)—O-substituted alkyl, —O(C═O)—O-aryl, —O(C═O)—O-substituted aryl, —O(SO₂)-alkyl, —O(SO₂)-substituted alkyl, —O(SO₂)-aryl, or —O(SO₂)-substituted aryl.

In another aspect, any of the embodiments presented herein may further comprise:

(i) arylating a compound of formula IVa,

to afford a compound of formula IV,

(ii) dihydroxylating IV,

to afford a compound of formula V or Va,

or a mixture thereof;

(iii) activating the primary alcohol of a compound of formula V or Va,

or a mixture thereof, to provide a compound of formula 2-7a or 2-7c,

or a mixture thereof; and

(iv) ring-closing of a compound of formula 2-7a or 2-7c,

or a mixture thereof, to afford a compound of formula of 5* or 5b*,

or a mixture thereof;

wherein R is

each R₂ is independently

halo, —O(C═O)-alkyl, —O(C═O)-substituted alkyl, —O(C═O)-aryl, —O(C═O)-substituted aryl, —O(C═O)—O-alkyl, —O(C═O)—O-substituted alkyl, —O(C═O)—O-aryl, —O(C═O)—O-substituted aryl, —O(SO₂)-alkyl, —O(SO₂)-substituted alkyl, —O(SO₂)-aryl, or —O(SO₂)-substituted aryl; and

each Y is independently OSO₂-alkyl, OSO₂-substituted alkyl, —OSO₂-aryl, —OSO₂-substituted aryl, —O(C═O)-alkyl, —O(C═O)-substituted alkyl, —O(C═O)-aryl, —O(C═O)-substituted aryl, or halogen.

In another aspect, Z from any of the embodiments presented herein is phenyl, p-tolyl, methyl, or ethyl.

In another aspect, any of the embodiments presented herein may further comprise:

(i) dihydroxylating a compound of formula IVa,

to afford a compound of formula Vb or Vc,

or a mixture thereof;

(ii) arylating a compound of formula Vb or Vc,

or a mixture thereof, to afford a compound of formula V or Va,

or a mixture thereof;

(iii) activating the primary alcohol of a compound of formula V or Va,

or a mixture thereof, to provide a compound of formula 2-7a or 2-7c,

or a mixture thereof; and

(iv) ring-closing of a compound of formula 2-7a or 2-7c.

or a mixture thereof, to afford a compound of formula of 5* or 5b*,

or a mixture thereof;

wherein R is

each R₂ is independently

halo, —O(C═O)-alkyl, —O(C═O)-substituted alkyl, —O(C═O)-aryl, —O(C═O)-substituted aryl, —O(C═O)—O-alkyl, —O(C═O)—O-substituted alkyl, —O(C═O)—O-aryl, —O(C═O)—O-substituted aryl, —O(SO₂)-alkyl, —O(SO₂)-substituted alkyl, —O(SO₂)-aryl, or —O(SO₂)-substituted aryl; and

-   -   each Y is independently —OSO₂-alkyl, OSO₂-substituted alkyl,         —OSO₂-aryl, —OSO₂-substituted aryl, —O(C═O)-alkyl,         —O(C═O)-substituted alkyl, —O(C═O)-aryl, —O(C═O)-substituted         aryl, or halogen.

In another aspect, any of the embodiments presented herein may further comprise:

(i) dihydroxylating a compound of formula IVa,

to afford a compound of formula Vb or Vc,

or a mixture thereof;

(ii) activating the primary alcohol of a compound of formula Vb or Vc,

or a mixture thereof, to afford a compound of formula VIb or VIc,

or a mixture thereof;

(iii) ring-closing of a compound of formula VIb or VIc,

or a mixture thereof, to provide a compound of formula VII or VIIa,

or a mixture thereof; and

(iv) arylating a compound of formula VII or VIIa,

or a mixture thereof, to afford a compound of formula 5* or 5b*,

or a mixture thereof;

wherein each R₂ is independently

halo, —O(C═O)-alkyl, —O(C═O)-substituted alkyl, —O(C═O)-aryl, —O(C═O)-substituted aryl, —O(C═O)—O-alkyl, —O(C═O)—O-substituted alkyl, —O(C═O)—O-aryl, —O(C═O)-O-substituted aryl, —O(SO₂)-alkyl, —O(SO₂)-substituted alkyl, —O(SO₂)-aryl, or —O(SO₂)-substituted aryl; and each Y is independently OSO₂-alkyl, —OSO₂-substituted alkyl, —OSO₂-aryl, —OSO₂-substituted aryl, —O(C═O)-alkyl, —O(C═O)-substituted alkyl, —O(C═O)-aryl, —O(C═O)-substituted aryl, or halogen.

In another aspect, any of the embodiments presented herein may further comprise:

(i) ring opening of a compound of formula VII or VIIa,

or a mixture thereof, to afford 1-6* or 1-7*,

or a mixture thereof;

wherein each R₂ is independently

halo, —O(C═O)-alkyl, —O(C═O)-substituted alkyl, —O(C═O)-aryl, —O(C═O)-substituted aryl, —O(C═O)—O-alkyl, —O(C═O)—O-substituted alkyl, —O(C═O)—O-aryl, —O(C═O)—O-substituted aryl, —O(SO₂)-alkyl, —O(SO₂)-substituted alkyl, —O(SO₂)-aryl, or —O(SO₂)-substituted aryl.

In another aspect, any of the embodiments presented herein may further comprise:

(i) forming the tetrazole of 1-6* or 1-7*,

or a mixture thereof to afford compound 1 or 1a, or a mixture thereof:

In another aspect, the crystalization solvent or crystallization solvent mixture from any of the embodiments presented herein is ethyl acetate, isopropyl acetate, ethanol, methanol, or acetonitrile, or combinations thereof.

In another aspect, the crystallization co-solvent or crystallization co-solvent mixture from any of the embodiments presented herein is pentane, methyl t-butylether, hexane, heptane, or toluene, or combinations thereof.

In another aspect, any of the embodiments presented herein may comprise repeating the enantio-enrichment step(s) until desired level of enantio-enrichment is attained.

In another aspect, Y in any of the embodiments presented herein may be mesylate or tosylate.

In another aspect, any of the embodiments presented herein may comprise substituting morpholine-amide 2b with amide 2c.

In another aspect, any of the embodiments presented herein may comprise substituting ethyl ester 2 with ester 2d. In other aspects, the invention provides a compound of any of the formulae herein, wherein the compound inhibits (or is identified to inhibit) lanosterol demethylase (CYP51).

In another aspect, the invention provides a pharmaceutical composition comprising a compound of any formulae herein and a pharmaceutically acceptable carrier.

In other aspects, the invention provides a method of modulating metalloenzyme activity in a subject, comprising contacting the subject with a compound of any formulae herein, in an amount and under conditions sufficient to modulate metalloenzyme activity.

In one aspect, the invention provides a method of treating a subject suffering from or susceptible to a metalloenzyme-related disorder or disease, comprising administering to the subject an effective amount of a compound or pharmaceutical composition of any formulae herein.

In another aspect, the invention provides a method of treating a subject suffering from or susceptible to a metalloenzyme-related disorder or disease, wherein the subject has been identified as in need of treatment for a metalloenzyme-related disorder or disease, comprising administering to said subject in need thereof, an effective amount of a compound or pharmaceutical composition of any formulae herein, such that said subject is treated for said disorder.

In another aspect, the invention provides a method of treating a subject suffering from or susceptible to a metalloenzyme-mediated disorder or disease, wherein the subject has been identified as in need of treatment for a metalloenzyme-mediated disorder or disease, comprising administering to said subject in need thereof, an effective amount of a compound or pharmaceutical composition of any formulae herein, such that metalloenzyme activity in said subject is modulated (e.g., down regulated, inhibited). In another aspect, the compounds delineated herein preferentially target cancer cells over nontransformed cells.

DETAILED DESCRIPTION Definitions

The term “chiral” refers to molecules which have the property of non-superimposability of the mirror image partner, while the term “achiral” refers to molecules which are superimposable on their mirror image partner.

The term “diastereomers” refers to stereoisomers with two or more centers of dissymmetry and whose molecules are not minor images of one another.

The term “enantiomers” refers to two stereoisomers of a compound which are non-superimposable minor images of one another. An equimolar mixture of two enantiomers is called a “racemic mixture” or a “racemate.”

The term “isomers” or “stereoisomers” refers to compounds which have identical chemical constitution, but differ with regard to the arrangement of the atoms or groups in space.

The term “prodrug” includes compounds with moieties which can be metabolized in vivo. Generally, the prodrugs are metabolized in vivo by esterases or by other mechanisms to active drugs. Examples of prodrugs and their uses are well known in the art (See, e.g., Berge et al. (1977) “Pharmaceutical Salts”, J. Pharm. Sci. 66:1-19). The prodrugs can be prepared in situ during the final isolation and purification of the compounds, or by separately reacting the purified compound in its free acid form or hydroxyl with a suitable esterifying agent. Hydroxyl groups can be converted into esters via treatment with a carboxylic acid. Examples of prodrug moieties include substituted and unsubstituted, branch or unbranched lower alkyl ester moieties, (e.g., propionoic acid esters), lower alkenyl esters, di-lower alkyl-amino lower-alkyl esters (e.g., dimethylaminoethyl ester), acylamino lower alkyl esters (e.g., acetyloxymethyl ester), acyloxy lower alkyl esters (e.g., pivaloyloxymethyl ester), aryl esters (phenyl ester), aryl-lower alkyl esters (e.g., benzyl ester), substituted (e.g., with methyl, halo, or methoxy substituents) aryl and aryl-lower alkyl esters, amides, lower-alkyl amides, di-lower alkyl amides, and hydroxy amides. Preferred prodrug moieties are propionoic acid esters and acyl esters. Prodrugs which are converted to active forms through other mechanisms in vivo are also included. In aspects, the compounds of the invention are prodrugs of any of the formulae herein.

The term “subject” refers to animals such as mammals, including, but not limited to, primates (e.g., humans), cows, sheep, goats, horses, dogs, cats, rabbits, rats, mice and the like. In certain embodiments, the subject is a human.

The terms “a,” “an,” and “the” refer to “one or more” when used in this application, including the claims. Thus, for example, reference to “a sample” includes a plurality of samples, unless the context clearly is to the contrary (e.g., a plurality of samples), and so forth.

Throughout this specification and the claims, the words “comprise,” “comprises,” and “comprising” are used in a non-exclusive sense, except where the context requires otherwise.

As used herein, the term “about,” when referring to a value is meant to encompass variations of, in some embodiments ±20%, in some embodiments ±10%, in some embodiments ±5%, in some embodiments ±1%, in some embodiments ±0.5%, and in some embodiments ±0.1% from the specified amount, as such variations are appropriate to perform the disclosed methods or employ the disclosed compositions.

Use of the word “inhibitor” herein is meant to mean a molecule that exhibits activity for inhibiting a metalloenzyme . By “inhibit” herein is meant to decrease the activity of metalloenzyme , as compared to the activity of metalloenzyme in the absence of the inhibitor. In some embodiments, the term “inhibit” means a decrease in metalloenzyme activity of at least about 5%, at least about 10%, at least about 20%, at least about 25%, at least about 50%, at least about 60%, at least about 70%, at least about 80%, at least about 90%, or at least about 95%. In other embodiments, inhibit means a decrease in metalloenzyme activity of about 5% to about 25%, about 25% to about 50%, about 50% to about 75%, or about 75% to 100%. In some embodiments, inhibit means a decrease in metalloenzyme activity of about 95% to 100%, e.g., a decrease in activity of 95%, 96%, 97%, 98%, 99%, or 100%. Such decreases can be measured using a variety of techniques that would be recognizable by one of skill in the art. Particular assays for measuring individual activity are described below.

Furthermore the compounds of the invention include olefins having either geometry:

“Z” refers to what is referred to as a “cis” (same side) configuration whereas “E” refers to what is referred to as a “trans” (opposite side) configuration. With respect to the nomenclature of a chiral center, the terms “d” and “1” configuration are as defined by the IUPAC Recommendations. As to the use of the terms, diastereomer, racemate, epimer and enantiomer, these will be used in their normal context to describe the stereochemistry of preparations.

As used herein, the term “alkyl” refers to a straight-chained or branched hydrocarbon group containing 1 to 12 carbon atoms. The term “lower alkyl” refers to a C1-C6 alkyl chain. Examples of alkyl groups include methyl, ethyl, n-propyl, isopropyl, tert-butyl, and n-pentyl. Alkyl groups may be optionally substituted with one or more substituents.

The term “alkenyl” refers to an unsaturated hydrocarbon chain that may be a straight chain or branched chain, containing 2 to 12 carbon atoms and at least one carbon-carbon double bond. Alkenyl groups may be optionally substituted with one or more substituents.

The term “alkynyl” refers to an unsaturated hydrocarbon chain that may be a straight chain or branched chain, containing the 2 to 12 carbon atoms and at least one carbon-carbon triple bond. Alkynyl groups may be optionally substituted with one or more substituents.

The sp² or sp carbons of an alkenyl group and an alkynyl group, respectively, may optionally be the point of attachment of the alkenyl or alkynyl groups.

The term “alkoxy” refers to an —O-alkyl radical.

As used herein, the term “halogen”, “hal” or “halo” means —F, —Cl, —Br or —I.

The term “haloalkoxy” refers to an -O-alkyl radical that is substituted by one or more halo substituents. Examples of haloalkoxy groups include trifluoromethoxy, and 2,2,2-trifluoroethoxy.

The term “cycloalkyl” refers to a hydrocarbon 3-8 membered monocyclic or 7-14 membered bicyclic ring system having at least one saturated ring or having at least one non-aromatic ring, wherein the non-aromatic ring may have some degree of unsaturation. Cycloalkyl groups may be optionally substituted with one or more substituents. In one embodiment, 0, 1, 2, 3, or 4 atoms of each ring of a cycloalkyl group may be substituted by a substituent. Representative examples of cycloalkyl group include cyclopropyl, cyclopentyl, cyclohexyl, cyclobutyl, cycloheptyl, cyclopentenyl, cyclopentadienyl, cyclohexenyl, cyclohexadienyl, and the like.

The term “aryl” refers to a hydrocarbon monocyclic, bicyclic or tricyclic aromatic ring system. Aryl groups may be optionally substituted with one or more substituents. In one embodiment, 0, 1, 2, 3, 4, 5 or 6 atoms of each ring of an aryl group may be substituted by a substituent. Examples of aryl groups include phenyl, naphthyl, anthracenyl, fluorenyl, indenyl, azulenyl, and the like.

The term “heteroaryl” refers to an aromatic 5-8 membered monocyclic, 8-12 membered bicyclic, or 11-14 membered tricyclic ring system having 1-4 ring heteroatoms if monocyclic, 1-6 heteroatoms if bicyclic, or 1-9 heteroatoms if tricyclic, said heteroatoms selected from O, N, or S, and the remainder ring atoms being carbon (with appropriate hydrogen atoms unless otherwise indicated). Heteroaryl groups may be optionally substituted with one or more substituents. In one embodiment, 0, 1, 2, 3, or 4 atoms of each ring of a heteroaryl group may be substituted by a substituent. Examples of heteroaryl groups include pyridyl, furanyl, thienyl, pyrrolyl, oxazolyl, oxadiazolyl, imidazolyl thiazolyl, isoxazolyl, quinolinyl, pyrazolyl, isothiazolyl, pyridazinyl, pyrimidinyl, pyrazinyl, triazinyl, isoquinolinyl, indazolyl, and the like.

The term “nitrogen-containing heteroaryl” refers to a heteroaryl group having 1-4 ring nitrogen heteroatoms if monocyclic, 1-6 ring nitrogen heteroatoms if bicyclic, or 1-9 ring nitrogen heteroatoms if tricyclic.

The term “heterocycloalkyl” refers to a nonaromatic 3-8 membered monocyclic, 7-12 membered bicyclic, or 10-14 membered tricyclic ring system comprising 1-3 heteroatoms if monocyclic, 1-6 heteroatoms if bicyclic, or 1-9 heteroatoms if tricyclic, said heteroatoms selected from O, N, S, B, P or Si, wherein the nonaromatic ring system is completely saturated. Heterocycloalkyl groups may be optionally substituted with one or more substituents. In one embodiment, 0, 1, 2, 3, or 4 atoms of each ring of a heterocycloalkyl group may be substituted by a substituent. Representative heterocycloalkyl groups include piperidinyl, piperazinyl, tetrahydropyranyl, morpholinyl, thiomorpholinyl, 1,3-dioxolane, tetrahydrofuranyl, tetrahydrothienyl, thiirenyl, and the like.

The term “alkylamino” refers to an amino substituent which is further substituted with one or two alkyl groups. The term “aminoalkyl” refers to an alkyl substituent which is further substituted with one or more amino groups. The term “hydroxyalkyl” or “hydroxylalkyl” refers to an alkyl substituent which is further substituted with one or more hydroxyl groups. The alkyl or aryl portion of alkylamino, aminoalkyl, mercaptoalkyl, hydroxyalkyl, mercaptoalkoxy, sulfonylalkyl, sulfonylaryl, alkylcarbonyl, and alkylcarbonylalkyl may be optionally substituted with one or more substituents.

Acids and bases useful in the methods herein are known in the art. Acid catalysts are any acidic chemical, which can be inorganic (e.g., hydrochloric, sulfuric, nitric acids, aluminum trichloride) or organic (e.g., camphorsulfonic acid, p-toluenesulfonic acid, acetic acid, ytterbium triflate) in nature. Acids are useful in either catalytic or stoichiometric amounts to facilitate chemical reactions. Bases are any basic chemical, which can be inorganic (e.g., sodium bicarbonate, potassium hydroxide) or organic (e.g., triethylamine, pyridine) in nature. Bases are useful in either catalytic or stoichiometric amounts to facilitate chemical reactions.

Alkylating agents are any reagent that is capable of effecting the alkylation of the functional group at issue (e.g., oxygen atom of an alcohol, nitrogen atom of an amino group). Alkylating agents are known in the art, including in the references cited herein, and include alkyl halides (e.g., methyl iodide, benzyl bromide or chloride), alkyl sulfates (e.g., methyl sulfate), or other alkyl group-leaving group combinations known in the art. Leaving groups are any stable species that can detach from a molecule during a reaction (e.g., elimination reaction, substitution reaction) and are known in the art, including in the references cited herein, and include halides (e.g., I—, Cl—, Br—, F—), hydroxy, alkoxy (e.g., —OMe, —O-t-Bu), acyloxy anions (e.g., —OAc, —OC(O)CF₃), sulfonates (e.g., mesyl, tosyl), acetamides (e.g., —NHC(O)Me), carbamates (e.g., N(Me)C(O)Ot-Bu), phosphonates (e.g., —OP(O)(OEt)₂), water or alcohols (protic conditions), and the like.

In certain embodiments, substituents on any group (such as, for example, alkyl, alkenyl, alkynyl, aryl, aralkyl, heteroaryl, heteroaralkyl, cycloalkyl, heterocycloalkyl) can be at any atom of that group, wherein any group that can be substituted (such as, for example, alkyl, alkenyl, alkynyl, aryl, aralkyl, heteroaryl, heteroaralkyl, cycloalkyl, heterocycloalkyl) can be optionally substituted with one or more substituents (which may be the same or different), each replacing a hydrogen atom. Examples of suitable substituents include, but are not limited to alkyl, alkenyl, alkynyl, cycloalkyl, heterocycloalkyl, aralkyl, heteroaralkyl, aryl, heteroaryl, halogen, haloalkyl, cyano, nitro, alkoxy, aryloxy, hydroxyl, hydroxylalkyl, oxo (i.e., carbonyl), carboxyl, formyl, alkylcarbonyl, alkylcarbonylalkyl, alkoxycarbonyl, alkylcarbonyloxy, aryloxycarbonyl, heteroaryloxy, heteroaryloxycarbonyl, thio, mercapto, mercaptoalkyl, arylsulfonyl, amino, aminoalkyl, dialkylamino, alkylcarbonylamino, alkylaminocarbonyl, alkoxycarbonylamino, alkylamino, arylamino, diarylamino, alkylcarbonyl, or arylamino-substituted aryl; arylalkylamino, aralkylaminocarbonyl, amido, alkylaminosulfonyl, arylaminosulfonyl, dialkylaminosulfonyl, alkylsulfonylamino, arylsulfonylamino, imino, carbamido, carbamyl, thioureido, thiocyanato, sulfoamido, sulfonylalkyl, sulfonylaryl, mercaptoalkoxy, N-hydroxyamidinyl, or N′-aryl, N″-hydroxyamidinyl.

Compounds of the invention can be made by means known in the art of organic synthesis. Methods for optimizing reaction conditions, if necessary minimizing competing by-products, are known in the art. Reaction optimization and scale-up may advantageously utilize high-speed parallel synthesis equipment and computer-controlled microreactors (e.g. Design And Optimization in Organic Synthesis, 2^(nd) Edition, Carlson R, Ed, 2005; Elsevier Science Ltd ; Jähnisch, K et al, Angew. Chem. Int. Ed. Engl. 2004 43: 406; and references therein). Additional reaction schemes and protocols may be determined by the skilled artesian by use of commercially available structure-searchable database software, for instance,

SciFinder® (CAS division of the American Chemical Society) and CrossFire Beilstein® (Elsevier MDL), or by appropriate keyword searching using an internet search engine such as Google® or keyword databases such as the US Patent and Trademark Office text database. The invention includes the intermediate compounds used in making the compounds of the formulae herein as well as methods of making such compounds and intermediates, including without limitation those as specifically described in the examples herein.

The compounds herein may also contain linkages (e.g., carbon-carbon bonds) wherein bond rotation is restricted about that particular linkage, e.g. restriction resulting from the presence of a ring or double bond. Accordingly, all cis/trans and E/Z isomers are expressly included in the present invention. The compounds herein may also be represented in multiple tautomeric forms, in such instances, the invention expressly includes all tautomeric forms of the compounds described herein, even though only a single tautomeric form may be represented. All such isomeric forms of such compounds herein are expressly included in the present invention. All crystal forms and polymorphs of the compounds described herein are expressly included in the present invention. Also embodied are extracts and fractions comprising compounds of the invention. The term isomers is intended to include diastereoisomers, enantiomers, regioisomers, structural isomers, rotational isomers, tautomers, and the like. For compounds which contain one or more stereogenic centers, e.g., chiral compounds, the methods of the invention may be carried out with an enantiomerically enriched compound, a racemate, or a mixture of diastereomers.

Preferred enantiomerically enriched compounds have an enantiomeric excess of 50% or more, more preferably the compound has an enantiomeric excess of 60%, 70%, 80%, 90%, 95%, 98%, or 99% or more. In preferred embodiments, only one enantiomer or diastereomer of a chiral compound of the invention is administered to cells or a subject.

Pharmaceutical Compositions

In one aspect, the invention provides a pharmaceutical composition comprising a compound of any formulae herein and a pharmaceutically acceptable carrier.

In another embodiment, the invention provides a pharmaceutical composition further comprising an additional therapeutic agent. In a further embodiment, the additional therapeutic agent is an anti-cancer agent, antifungal agent, cardiovascular agent, antiinflammatory agent, chemotherapeutic agent, an anti-angiogenesis agent, cytotoxic agent, an anti-proliferation agent, metabolic disease agent, opthalmologic disease agent, central nervous system (CNS) disease agent, urologic disease agent, or gastrointestinal disease agent.

In one aspect, the invention provides a kit comprising an effective amount of a compound of any formulae herein, in unit dosage form, together with instructions for administering the compound to a subject suffering from or susceptible to a metalloenzyme-mediated disease or disorder, including cancer, solid tumor, cardiovascular disease, inflammatory disease, infectious disease. In other embodiments the disease, disorder or symptom thereof is metabolic disease, opthalmologic disease, central nervous system (CNS) disease, urologic disease, or gastrointestinal disease.

The term “pharmaceutically acceptable salts” or “pharmaceutically acceptable carrier” is meant to include salts of the active compounds which are prepared with relatively nontoxic acids or bases, depending on the particular substituents found on the compounds described herein. When compounds of the present invention contain relatively acidic functionalities, base addition salts can be obtained by contacting the neutral form of such compounds with a sufficient amount of the desired base, either neat or in a suitable inert solvent. Examples of pharmaceutically acceptable base addition salts include sodium, potassium, calcium, ammonium, organic amino, or magnesium salt, or a similar salt. When compounds of the present invention contain relatively basic functionalities, acid addition salts can be obtained by contacting the neutral form of such compounds with a sufficient amount of the desired acid, either neat or in a suitable inert solvent. Examples of pharmaceutically acceptable acid addition salts include those derived from inorganic acids like hydrochloric, hydrobromic, nitric, carbonic, monohydrogencarbonic, phosphoric, monohydrogenphosphoric, dihydrogenphosphoric, sulfuric, monohydrogensulfuric, hydroiodic, or phosphorous acids and the like, as well as the salts derived from relatively nontoxic organic acids like acetic, propionic, isobutyric, maleic, malonic, benzoic, succinic, suberic, fumaric, lactic, mandelic, phthalic, benzenesulfonic, p-tolylsulfonic, citric, tartaric, methanesulfonic, and the like. Also included are salts of amino acids such as arginate and the like, and salts of organic acids like glucuronic or galactunoric acids and the like (see, e.g., Berge et al., Journal of Pharmaceutical Science 66:1-19 (1977)). Certain specific compounds of the present invention contain both basic and acidic functionalities that allow the compounds to be converted into either base or acid addition salts. Other pharmaceutically acceptable carriers known to those of skill in the art are suitable for the present invention.

The neutral forms of the compounds may be regenerated by contacting the salt with a base or acid and isolating the parent compound in the conventional manner. The parent form of the compound differs from the various salt forms in certain physical properties, such as solubility in polar solvents, but otherwise the salts are equivalent to the parent form of the compound for the purposes of the present invention.

In addition to salt forms, the present invention provides compounds which are in a prodrug form. Prodrugs of the compounds described herein are those compounds that readily undergo chemical changes under physiological conditions to provide the compounds of the present invention. Additionally, prodrugs can be converted to the compounds of the present invention by chemical or biochemical methods in an ex vivo environment. For example, prodrugs can be slowly converted to the compounds of the present invention when placed in a transdermal patch reservoir with a suitable enzyme or chemical reagent.

Certain compounds of the present invention can exist in unsolvated forms as well as solvated forms, including hydrated forms. In general, the solvated forms are equivalent to unsolvated forms and are intended to be encompassed within the scope of the present invention. Certain compounds of the present invention may exist in multiple crystalline or amorphous forms. In general, all physical forms are equivalent for the uses contemplated by the present invention and are intended to be within the scope of the present invention.

The invention also provides a pharmaceutical composition, comprising an effective amount a compound described herein and a pharmaceutically acceptable carrier. In an embodiment, compound is administered to the subject using a pharmaceutically-acceptable formulation, e.g., a pharmaceutically-acceptable formulation that provides sustained delivery of the compound to a subject for at least 12 hours, 24 hours, 36 hours, 48 hours, one week, two weeks, three weeks, or four weeks after the pharmaceutically-acceptable formulation is administered to the subject.

Actual dosage levels and time course of administration of the active ingredients in the pharmaceutical compositions of this invention may be varied so as to obtain an amount of the active ingredient which is effective to achieve the desired therapeutic response for a particular patient, composition, and mode of administration, without being toxic (or unacceptably toxic) to the patient.

In use, at least one compound according to the present invention is administered in a pharmaceutically effective amount to a subject in need thereof in a pharmaceutical carrier by intravenous, intramuscular, subcutaneous, or intracerebro ventricular injection or by oral administration or topical application. In accordance with the present invention, a compound of the invention may be administered alone or in conjunction with a second, different therapeutic.

By “in conjunction with” is meant together, substantially simultaneously or sequentially. In one embodiment, a compound of the invention is administered acutely. The compound of the invention may therefore be administered for a short course of treatment, such as for about 1 day to about 1 week. In another embodiment, the compound of the invention may be administered over a longer period of time to ameliorate chronic disorders, such as, for example, for about one week to several months depending upon the condition to be treated.

By “pharmaceutically effective amount” as used herein is meant an amount of a compound of the invention, high enough to significantly positively modify the condition to be treated but low enough to avoid serious side effects (at a reasonable benefit/risk ratio), within the scope of sound medical judgment. A pharmaceutically effective amount of a compound of the invention will vary with the particular goal to be achieved, the age and physical condition of the patient being treated, the severity of the underlying disease, the duration of treatment, the nature of concurrent therapy and the specific compound employed. For example, a therapeutically effective amount of a compound of the invention administered to a child or a neonate will be reduced proportionately in accordance with sound medical judgment. The effective amount of a compound of the invention will thus be the minimum amount which will provide the desired effect.

A decided practical advantage of the present invention is that the compound may be administered in a convenient manner such as by intravenous, intramuscular, subcutaneous, oral or intra-cerebroventricular injection routes or by topical application, such as in creams or gels. Depending on the route of administration, the active ingredients which comprise a compound of the invention may be required to be coated in a material to protect the compound from the action of enzymes, acids and other natural conditions which may inactivate the compound. In order to administer a compound of the invention by other than parenteral administration, the compound can be coated by, or administered with, a material to prevent inactivation.

The compound may be administered parenterally or intraperitoneally. Dispersions can also be prepared, for example, in glycerol, liquid polyethylene glycols, and mixtures thereof, and in oils.

Some examples of substances which can serve as pharmaceutical carriers are sugars, such as lactose, glucose and sucrose; starches such as corn starch and potato starch; cellulose and its derivatives such as sodium carboxymethycellulose, ethylcellulose and cellulose acetates; powdered tragancanth; malt; gelatin; talc; stearic acids; magnesium stearate; calcium sulfate; vegetable oils, such as peanut oils, cotton seed oil, sesame oil, olive oil, corn oil and oil of theobroma; polyols such as propylene glycol, glycerine, sorbitol, manitol, and polyethylene glycol; agar; alginic acids; pyrogen-free water; isotonic saline; and phosphate buffer solution; skim milk powder; as well as other non-toxic compatible substances used in pharmaceutical formulations such as Vitamin C, estrogen and echinacea, for example. Wetting agents and lubricants such as sodium lauryl sulfate, as well as coloring agents, flavoring agents, lubricants, excipients, tableting agents, stabilizers, anti-oxidants and preservatives, can also be present. Solubilizing agents, including for example, cremaphore and beta-cyclodextrins can also used in the pharmaceutical compositions herein.

Pharmaceutical compositions comprising the active compounds of the presently disclosed subject matter (or prodrugs thereof) can be manufactured by means of conventional mixing, dissolving, granulating, dragee-making levigating, emulsifying, encapsulating, entrapping or lyophilization processes. The compositions can be formulated in conventional manner using one or more physiologically acceptable carriers, diluents, excipients or auxiliaries which facilitate processing of the active compounds into preparations which can be used pharmaceutically.

Pharmaceutical compositions of the presently disclosed subject matter can take a form suitable for virtually any mode of administration, including, for example, topical, ocular, oral, buccal, systemic, nasal, injection, transdermal, rectal, vaginal, and the like, or a form suitable for administration by inhalation or insufflation.

For topical administration, the active compound(s) or prodrug(s) can be formulated as solutions, gels, ointments, creams, suspensions, and the like.

Systemic formulations include those designed for administration by injection, e.g., subcutaneous, intravenous, intramuscular, intrathecal or intraperitoneal injection, as well as those designed for transdermal, transmucosal, oral, or pulmonary administration.

Useful injectable preparations include sterile suspensions, solutions or emulsions of the active compound(s) in aqueous or oily vehicles. The compositions also can contain formulating agents, such as suspending, stabilizing and/or dispersing agent. The formulations for injection can be presented in unit dosage form (e.g., in ampules or in multidose containers) and can contain added preservatives.

Alternatively, the injectable formulation can be provided in powder form for reconstitution with a suitable vehicle, including but not limited to sterile pyrogen free water, buffer, dextrose solution, and the like, before use. To this end, the active compound(s) can be dried by any art-known technique, such as lyophilization, and reconstituted prior to use.

For transmucosal administration, penetrants appropriate to the barrier to be permeated are used in the formulation. Such penetrants are known in the art.

For oral administration, the pharmaceutical compositions can take the form of, for example, lozenges, tablets or capsules prepared by conventional means with pharmaceutically acceptable excipients such as binding agents (e.g., pregelatinized maize starch, polyvinylpyrrolidone or hydroxypropyl methylcellulose); fillers (e.g., lactose, microcrystalline cellulose or calcium hydrogen phosphate); lubricants (e.g., magnesium stearate, talc or silica); disintegrants (e.g., potato starch or sodium starch glycolate); or wetting agents (e.g., sodium lauryl sulfate). The tablets can be coated by methods well known in the art with, for example, sugars or enteric coatings.

Liquid preparations for oral administration can take the form of, for example, elixirs, solutions, syrups or suspensions, or they can be presented as a dry product for constitution with water or other suitable vehicle before use. Such liquid preparations can be prepared by conventional means with pharmaceutically acceptable additives such as suspending agents (e.g., sorbitol syrup, cellulose derivatives or hydrogenated edible fats); emulsifying agents (e.g., lecithin or acacia); non aqueous vehicles (e.g., almond oil, oily esters, ethyl alcohol or fractionated vegetable oils); and preservatives (e.g., methyl or propyl p-hydroxybenzoates or sorbic acid). The preparations also can contain buffer salts, preservatives, flavoring, coloring and sweetening agents as appropriate.

Preparations for oral administration can be suitably formulated to give controlled release of the active compound or prodrug, as is well known.

For buccal administration, the compositions can take the form of tablets or lozenges formulated in a conventional manner.

For rectal and vaginal routes of administration, the active compound(s) can be formulated as solutions (for retention enemas), suppositories, or ointments containing conventional suppository bases, such as cocoa butter or other glycerides.

For nasal administration or administration by inhalation or insufflation, the active compound(s) or prodrug(s) can be conveniently delivered in the form of an aerosol spray from pressurized packs or a nebulizer with the use of a suitable propellant, e.g., dichlorodifluoromethane, trichlorofluoromethane, dichlorotetrafluoroethane, fluorocarbons, carbon dioxide or other suitable gas. In the case of a pressurized aerosol, the dosage unit can be determined by providing a valve to deliver a metered amount. Capsules and cartridges for use in an inhaler or insufflator (for example capsules and cartridges comprised of gelatin) can be formulated containing a powder mix of the compound and a suitable powder base such as lactose or starch.

A specific example of an aqueous suspension formulation suitable for nasal administration using commercially-available nasal spray devices includes the following ingredients: active compound or prodrug (0.5-20 mg/ml); benzalkonium chloride (0.1-0.2 mg/mL); polysorbate 80 (TWEEN® 80; 0.5-5 mg/ml); carboxymethylcellulose sodium or microcrystalline cellulose (1-15 mg/ml); phenylethanol (1-4 mg/ml); and dextrose (20-50 mg/ml). The pH of the final suspension can be adjusted to range from about pH5 to pH7, with a pH of about pH 5.5 being typical.

For prolonged delivery, the active compound(s) or prodrug(s) can be formulated as a depot preparation for administration by implantation or intramuscular injection. The active ingredient can be formulated with suitable polymeric or hydrophobic materials (e.g., as an emulsion in an acceptable oil) or ion exchange resins, or as sparingly soluble derivatives, e.g., as a sparingly soluble salt. Alternatively, transdermal delivery systems manufactured as an adhesive disc or patch which slowly releases the active compound(s) for percutaneous absorption can be used. To this end, permeation enhancers can be used to facilitate transdermal penetration of the active compound(s). Suitable transdermal patches are described in for example, U.S. Pat. No. 5,407,713; U.S. Pat. No. 5,352,456; U.S. Pat. No. 5,332,213; U.S. Pat. No. 5,336,168; U.S. Pat. No. 5,290,561; U.S. Pat. No. 5,254,346; U.S. Pat. No. 5,164,189; U.S. Pat. No. 5,163,899; U.S. Pat. No. 5,088,977; U.S. Pat. No. 5,087,240; U.S. Pat. No. 5,008,110; and U.S. Pat. No. 4,921,475, each of which is incorporated herein by reference in its entirety.

Alternatively, other pharmaceutical delivery systems can be employed. Liposomes and emulsions are well-known examples of delivery vehicles that can be used to deliver active compound(s) or prodrug(s). Certain organic solvents such as dimethylsulfoxide (DMSO) also can be employed.

The pharmaceutical compositions can, if desired, be presented in a pack or dispenser device which can contain one or more unit dosage forms containing the active compound(s). The pack can, for example, comprise metal or plastic foil, such as a blister pack. The pack or dispenser device can be accompanied by instructions for administration.

The active compound(s) or prodrug(s) of the presently disclosed subject matter, or compositions thereof, will generally be used in an amount effective to achieve the intended result, for example in an amount effective to treat or prevent the particular disease being treated. The compound(s) can be administered therapeutically to achieve therapeutic benefit or prophylactically to achieve prophylactic benefit. By therapeutic benefit is meant eradication or amelioration of the underlying disorder being treated and/or eradication or amelioration of one or more of the symptoms associated with the underlying disorder such that the patient reports an improvement in feeling or condition, notwithstanding that the patient can still be afflicted with the underlying disorder. For example, administration of a compound to a patient suffering from an allergy provides therapeutic benefit not only when the underlying allergic response is eradicated or ameliorated, but also when the patient reports a decrease in the severity or duration of the symptoms associated with the allergy following exposure to the allergen. As another example, therapeutic benefit in the context of asthma includes an improvement in respiration following the onset of an asthmatic attack, or a reduction in the frequency or severity of asthmatic episodes. Therapeutic benefit also includes halting or slowing the progression of the disease, regardless of whether improvement is realized.

For prophylactic administration, the compound can be administered to a patient at risk of developing one of the previously described diseases. A patient at risk of developing a disease can be a patient having characteristics placing the patient in a designated group of at risk patients, as defined by an appropriate medical professional or group. A patient at risk may also be a patient that is commonly or routinely in a setting where development of the underlying disease that may be treated by administration of a metalloenzyme inhibitor according to the invention could occur. In other words, the at risk patient is one who is commonly or routinely exposed to the disease or illness causing conditions or may be acutely exposed for a limited time. Alternatively, prophylactic administration can be applied to avoid the onset of symptoms in a patient diagnosed with the underlying disorder.

The amount of compound administered will depend upon a variety of factors, including, for example, the particular indication being treated, the mode of administration, whether the desired benefit is prophylactic or therapeutic, the severity of the indication being treated and the age and weight of the patient, the bioavailability of the particular active compound, and the like. Determination of an effective dosage is well within the capabilities of those skilled in the art.

Effective dosages can be estimated initially from in vitro assays. For example, an initial dosage for use in animals can be formulated to achieve a circulating blood or serum concentration of active compound that is at or above an IC50 of the particular compound as measured in as in vitro assay, such as the in vitro fungal MIC or MFC and other in vitro assays described in the Examples section. Calculating dosages to achieve such circulating blood or serum concentrations taking into account the bioavailability of the particular compound is well within the capabilities of skilled artisans. For guidance, see Fingl & Woodbury, “General Principles,” In: Goodman and Gilman's The Pharmaceutical Basis of Therapeutics, Chapter 1, pp. 1-46, latest edition, Pagamonon Press, and the references cited therein, which are incorporated herein by reference.

Initial dosages also can be estimated from in vivo data, such as animal models. Animal models useful for testing the efficacy of compounds to treat or prevent the various diseases described above are well-known in the art.

Dosage amounts will typically be in the range of from about 0.0001 or 0.001 or 0.01 mg/kg/day to about 100 mg/kg/day, but can be higher or lower, depending upon, among other factors, the activity of the compound, its bioavailability, the mode of administration, and various factors discussed above. Dosage amount and interval can be adjusted individually to provide plasma levels of the compound(s) which are sufficient to maintain therapeutic or prophylactic effect. In cases of local administration or selective uptake, such as local topical administration, the effective local concentration of active compound(s) cannot be related to plasma concentration. Skilled artisans will be able to optimize effective local dosages without undue experimentation.

The compound(s) can be administered once per day, a few or several times per day, or even multiple times per day, depending upon, among other things, the indication being treated and the judgment of the prescribing physician.

Preferably, the compound(s) will provide therapeutic or prophylactic benefit without causing substantial toxicity. Toxicity of the compound(s) can be determined using standard pharmaceutical procedures. The dose ratio between toxic and therapeutic (or prophylactic) effect is the therapeutic index. Compounds(s) that exhibit high therapeutic indices are preferred.

The recitation of a listing of chemical groups in any definition of a variable herein includes definitions of that variable as any single group or combination of listed groups. The recitation of an embodiment for a variable herein includes that embodiment as any single embodiment or in combination with any other embodiments or portions thereof. The recitation of an embodiment herein includes that embodiment as any single embodiment or in combination with any other embodiments or portions thereof.

Another object of the present invention is the use of a compound as described herein (e.g., of any formulae herein) in the manufacture of a medicament for use in the treatment of a metalloenzyme-mediated disorder or disease. Another object of the present invention is the use of a compound as described herein (e.g., of any formulae herein) for use in the treatment of a metalloenzyme-mediated disorder or disease. Another object of the present invention is the use of a compound as described herein (e.g., of any formulae herein) in the manufacture of an agricultural composition for use in the treatment or prevention of a metalloenzyme-mediated disorder or disease in agricultural or agrarian settings.

Agricultural Applications

The compounds and compositions herein can be used in methods of modulating metalloenzyme activity in a microorganism on a plant comprising contacting a compound (or composition) herein with the plant (e.g., seed, seedling, grass, weed, grain). The compounds and compositions herein can be used to treat a plant, field or other agricultural area (e.g., as herbicides, pesticides, growth regulators, etc.) by administering the compound or composition (e.g., contacting, applying, spraying, atomizing, dusting, etc.) to the subject plant, field or other agricultural area. The administration can be either pre- or post-emergence. The administration can be either as a treatment or preventative regimen.

Examples

The present invention will now be demonstrated using specific examples that are not to be construed as limiting.

General Experimental Procedures

Definitions of variables in the structures in schemes herein are commensurate with those of corresponding positions in the formulae delineated herein.

Synthesis of 1 or 1a

A process to prepare enantiopure compound 1 or la is disclosed. Syntheses of for la may be accomplished using the example syntheses that are shown below (Schemes 1-4). The preparation of precursor ketone 3-Br is performed starting with reaction of 2,5-dibromo-pyridine with ethyl 2-bromo-difluoroacetate to produce ester 2-Br. This ester can be reacted with morpholine to furnish morpholine amide 2b-Br, followed by arylation to provide ketone 3-Br. Alternatively, ketone 3-Br can be afforded directly from ester 2-Br as shown in Scheme 1.

Ketone 3 may be prepared in an analogous fashion as described in Scheme 1 starting from corresponding substituted 2-bromo-pyridines, which can be prepared according to synthetic transformations known in the art and contained in the references cited herein (Scheme 2).

Alternatively, compound 1 can be prepared according to Scheme 3 utilizing diols 2-6b (or 2-6d, the enantiomer of 2-6b, or mixtures thereof) or 2-6a (or 2-6c, the enantiomer of 2-6a, or mixtures thereof). Olefins 2-5a and 2-5 can be prepared by reacting ketones 3 and 1-4 under Wittig olefination conditions (e.g., Ph₃PCH₃Br and BuLi). Also, as indicated in Scheme 5, any of pyridine compounds, 3, 2-5a, 2-6b, 2-7b, 4*, 4b, or 6 can be converted to the corresponding 4-CF₃CH₂O—Ph analogs (e.g., 1-4, 2-5, 2-6a, 2-7a, 5*, 1-6*, or 1 or the corresponding enantiomers, or mixtures thereof) by cross-coupling with 4,4,5,5-tetramethyl-2-(4-(2,2,2-trifluoroethoxy)phenyl)-1,3,2-dioxaborolane (or the corresponding alkyl boronates or boronic acid or the like), in a suitable solvent system (e.g., an organic-aqueous solvent mixture), in the presence of a transition metal catalyst (e.g., (dppf)PdC1₂), and in the presence of a base (e.g., KHCO₃, K₂CO₃, Cs₂CO₃, or Na₂CO₃, or the like). Olefins 2-5a and 2-5 can be transformed to the corresponding chiral diols, 2-6b (or 2-6d, the enantiomer of 2-6b, or mixtures thereof) or 2-6a (or 2-6c, the enantiomer of 2-6a, or mixtures thereof), through exposure to Sharpless asymmetric dihydroxylation conditions: 1) commercially available AD-mix alpha or AD-mix beta with or without additional osmium oxidant and methanesulfonamide, 2) combination of a catalytic osmium oxidant (e.g., OsO₄ or K₂OsO₂(OH)₄), a stoichiometric iron oxidant (e.g., K₃Fe(CN)₆), a base (e.g., KHCO₃, K₂CO₃, Cs₂CO₃, or Na₂CO₃, or the like), and a chiral ligand (e.g., (DHQ)₂PHAL, (DHQD)₂PHAL, (DHQD)₂AQN, (DHQ)2AQN, (DHQD)₂PYR, or (DHQ)2PYR; preferably (DHQ)2PHAL,

(DHQD)₂PHAL, (DHQD)₂AQN, and (DHQD)₂PYR), or 3) option 2) with methanesulfonamide. The primary alcohol of the resultant chiral diols, 2-6b (or 2-6d, the enantiomer of 2-6b, or mixtures thereof) or 2-6a (or 2-6c, the enantiomer of 2-6a, or mixtures thereof), can then be activated to afford compounds 2-7b (or 2-7d, the enantiomer of 2-7b, or mixtures thereof) or 2-7a (or 2-7c, the enantiomer of 2-7a, or mixtures thereof). For example, the mesylates can be prepared by exposing chiral diols, 2-6b (or 2-6d, the enantiomer of 2-6b, or mixtures thereof) or 2-6a (or 2-6c, the enantiomer of 2-6a, or mixtures thereof), to methanesulfonyl chloride and a base. Epoxide formation can be affected by the base-mediated (e.g., KHCO₃, K₂CO₃, Cs₂CO₃, or Na₂CO₃, or the like) ring closure of compounds 2-7b (or 2-7d, the enantiomer of 2-7b, or mixtures thereof) or 2-7a (or 2-7c, the enantiomer of 2-7a, or mixtures thereof) to provide epoxides 4* (or 4c*, the enantiomer of 4*, or mixtures thereof) and 5* (or 5-b*, the enantiomer of 5*, or mixtures thereof). The epoxides can then be converted into amino-alcohols 4b (or 4c, the enantiomer of 4b, or mixtures thereof) and 1-6* (or 1-7*, the enantiomer of 1-6*, or mixtures thereof) through ammonia-mediated epoxide opening using ammonia in a suitable solvent (e.g., MeOH, EtOH, or water). Subsequent treatment with TMS-azide in the presence of trimethylorthoformate and sodium acetate in acetic acid would yield compounds 6 (or 6a, the enantiomer of 6, or mixtures thereof) or 1 (or 1a, the enantiomer of 1, or mixtures thereof) (U.S. Pat. No. 4,426,531).

Compound 1 (or 1a, the enantiomer of 1, or mixtures thereof) prepared by any of the methods presented herein can be converted to a sulfonic salt of formula IX (or IXa, the enantiomer of IX, or mixtures thereof), as shown in Scheme 4. This can be accomplished by a) combining compound 1 (or 1a, the enantiomer of 1, or mixtures thereof), a crystallization solvent or crystallization solvent mixture (e.g., EtOAc, iPrOAc, EtOH, MeOH, or acetonitrile, or combinations thereof), and a sulfonic acid

(e.g., Z═Ph, p-tolyl, Me, or Et), b) diluting the mixture with an appropriate crystallization co-solvent or crystallization co-solvent mixture (e.g., pentane, methyl t-butylether, hexane, heptane, or toluene, or combinations thereof), and c) filtering the mixture to obtain a sulfonic acid salt of formula IX (or IXa, the enantiomer of IX, or mixtures thereof).

The following describes the HPLC method used in assessing HPLC purity of the examples and intermediates presented below:

Column: Waters XBridge Shield RP18, 4.6×150 mm, 3.5 μm

Mobile Phase: A=0.05% TFA/H₂O, B=0.05% TFA/ACN

Autosampler flush: 1:1 ACN/H₂O

Diluent: 1:1 ACN/H₂O

Flow Rate: 1.0 ml/min

Temperature: 45° C.

Detector: UV 275 nm

Pump Parameters Step Segment Time A B Curve 0 0.5 80.0 20.0 0 1 15.0 60.0 40.0 1 2 10.0 15.0 85.0 1 3 5.0 0.0 100.0 1 4 2.0 0.0 100.0 0 5 8.0 80.0 20.0 0

EXAMPLE 1 Preparation of ethyl 2-(5-bromopyridin-2-yl)-2,2-difluoroacetate (2-Br)

In a clean multi-neck round bottom flask, copper powder (274.7 g, 2.05 eq) was suspended in dimethyl sulfoxide (3.5 L, 7 vol) at 20-35° C. Ethyl bromodifluoroacetate (449 g, 1.05 eq) was slowly added to the reaction mixture at 20-25° C. and stirred for 1-2 h. 2, 5-dibromopyridine (500 g, 1 eq) was added to the reaction mixture and the temperature was increased to 35-40 ° C. The reaction mixture was maintained at this temperature for 18-24 h and the reaction progress was monitored by GC.

After the completion of the reaction, ethyl acetate (7 L, 14 vol) was added to the reaction mixture and stirring was continued for 60-90 min at 20-35° C. The reaction mixture was filtered through a Celite bed (100 g; 0.2 times w/w Celite and 1L; 2 vol ethyl acetate). The reactor was washed with ethyl acetate (6 L, 12 vol) and the washings were filtered through a

Celite bed. The Celite bed was finally washed with ethyl acetate (1 L, 2 vol) and all the filtered mother liquors were combined. The pooled ethyl acetate solution was cooled to 8-10° C., washed with the buffer solution (5 L, 10 vol) below 15° C. (Note: The addition of buffer solution was exothermic in nature. Controlled addition of buffer was required to maintain the reaction mixture temperature below 15° C.). The ethyl acetate layer was washed again with the buffer solution until (7.5 L; 3×5 vol) the aqueous layer remained colorless. The organic layer was washed with a 1:1 solution of 10% w/w aqueous sodium chloride and the buffer solution (2.5 L; 5 vol). The organic layer was then transferred into a dry reactor and the ethyl acetate was distilled under reduced pressure to get crude 2-Br.

The crude 2-Br was purified by high vacuum fractional distillation and the distilled fractions having 2-Br purity greater than 93% (with the dialkylated not more than 2% and starting material less than 0.5%) were pooled together to afford 2-Br.

Yield after distillation: 47.7% with >93% purity by GC (pale yellow liquid). Another 10% yield was obtained by re-distillation of impure fractions resulting in overall yield of ˜55-60%.

¹H NMR: δ values with respect to TMS (DMSO-d₆; 400 MHz): 8.85; (1H, d, 1.6 Hz), 8.34; (1H, dd, J=2.0 Hz, 6.8 Hz), 7.83; (1H, d, J=6.8 Hz), 4.33; (2H, q, J=6.0 Hz), 1.22; (3H, t, J=6.0 Hz). ¹³C NMR: 162.22 (t, —C═O), 150.40 (Ar—C—), 149.35; (t, Ar—C), 140.52; (Ar—C), 123.01; (Ar—C), 122.07; (Ar—C), 111.80; (t, —CF₂), 63.23; (—OCH₂—), 13.45; (—CH₂CH₃).

EXAMPLE 2 Preparation of 2-(5-bromopyridin-2-yl)-1-(2,4-difluorophenyl)-2,2-difluoroethanone (3-Br) A. One-Step Method

1-Bromo-2,4-difluorobenzene (268.7 g; 1.3 eq) was dissolved in methyl tert butyl ether (MTBE, 3.78 L, 12.6 vol) at 20-35° C. and the reaction mixture was cooled to −70 to −65° C. using acetone/dry ice bath. n-Butyl lithium (689 mL, 1.3 eq; 2.5 M) was then added to the reaction mixture maintaining the reaction temperature below −65° C. (Note: Controlled addition of the n-Butyl Lithium to the reaction mixture was needed to maintain the reaction mixture temperature below −65° C.). After maintaining the reaction mixture at this temperature for 30-45 min, 2-Br (300 g, 1 eq) dissolved in MTBE (900 mL, 3 vol) was added to the reaction mixture below −65° C. The reaction mixture was continued to stir at this temperature for 60-90 min and the reaction progress was monitored by GC. The reaction was quenched by slow addition of 20% w/w ammonium chloride solution (750 mL, 2.5 vol) below −65° C. The reaction mixture was gradually warmed to 20-35° C. and an additional amount of 20% w/w ammonium chloride solution (750 mL, 2.5 vol) was added. The aqueous layer was separated, the organic layer was washed with a 10% w/w sodium bicarbonate solution (600 mL, 2 vol) followed by a 5% sodium chloride wash (600 mL, 2 vol). The organic layer was dried over sodium sulfate (60 g; 0.2 times w/w), filtered and the sodium sulfate was washed with MTBE (300 mL, 1 vol). The organic layer along with washings was distilled below 45° C. under reduced pressure until no more solvent was collected in the receiver. The distillation temperature was increased to 55-60° C., maintained under vacuum for 3-4 h and cooled to 20-35° C. to afford 275 g (73.6% yield, 72.71% purity by HPLC) of 3-Br as a pale yellow liquid.

¹H NMR: δ values with respect to TMS (DMSO-d₆; 400 MHz):8.63; (1H, d, 1.6 Hz, Ar—H), 8.07-8.01; (2H, m, 2 x Ar—H), 7.72; (1H, d, J=6.8 Hz, Ar—H), 7.07-6.82; (1H, m, Ar—H), 6.81-6.80; (1H, m, Ar—H). ¹³C NMR:185.60; (t, —C═O), 166.42; (dd, Ar—C—), 162.24; (dd, Ar—C), 150.80; (Ar—C), 150.35; (Ar—C), 140.02; (Ar—C), 133.82; (Ar—C), 123.06; (Ar—C), 1122.33; (Ar—C), 118.44; (Ar—C), 114.07; (—CF₂—), 122.07; (Ar—C), 105.09; (Ar—C).

B. Two-Step Method via 2b-Br

2-Br (147.0 g) was dissolved in n-heptane (1.21 L) and transferred to a 5-L reactor equipped with overhead stirrer, thermocouple, condenser and addition funnel. Morpholine (202 ml) was added. The solution was heated to 60° C. and stirred overnight. The reaction was complete by HPLC analysis (0.2% 2-Br; 94.7% 2b-Br). The reaction was cooled to room temperature and 1.21 L of MTBE was added. The solution was cooled to ˜4° C. and quenched by slow addition of 30% citric acid (563 ml) to maintain the internal temperature <15° C. After stirring for one hour the layers were allowed to settle and were separated (Aq. pH=5). The organic layer was washed with 30% citric acid (322 ml) and 9% NaHCO₃ (322 ml, aq. pH 7+ after separation). The organic layer was concentrated on the rotary evaporator (Note 1) to 454 g (some precipitation started immediately and increased during concentration). After stirring at room temperature the suspension was filtered and the product cake was washed with n-heptane (200 ml). The solid was dried in a vacuum oven at room temperature to provide 129.2 g (77%) dense powder. The purity was 96.5% by HPLC analysis.

To a 1-L flask equipped with overhead stirring, thermocouple, condenser and addition funnel was added magnesium turnings (14.65 g), THF (580 ml) and 1-bromo-2,4-difluorobenzene (30.2 g, 0.39 equiv). The mixture was stirred until the reaction initiated and self-heating brought the reaction temperature to 44° C. The temperature was controlled with a cooling bath as the remaining 1-bromo-2,4-difluorobenzene (86.1 g, 1.11 equiv) was added over about 30 min. at an internal temperature of 35-40° C. The reaction was stirred for 2 hours while gradually cooling to room temperature. The dark yellow solution was further cooled to 12° C.

During the Grignard formation, a jacketed 2-L flask equipped with overhead stirring, thermocouple, and addition funnel was charged with morpholine amide 2b-Br (129.0 g) and THF (645 ml). The mixture was stirred at room temperature until the solid dissolved, and then the solution was cooled to −8.7° C. The Grignard solution was added via addition funnel over about 30 min at a temperature of −5 to 0° C. The reaction was stirred at 0° C. for 1 hour and endpointed by HPLC analysis. The reaction mixture was cooled to −5° C. and quenched by slow addition of 2N HCl over 1 hour at ≦10° C. The mixture was stirred for 0.5 h then the layers were allowed to settle and were separated. The aqueous layer was extracted with MTBE (280 ml). The combined organic layers were washed with 9% NaHCO₃ (263 g) and 20% NaCl (258 ml). The organic layer was concentrated on the rotary evaporator with THF rinses to transfer all the solution to the distillation flask. Additional THF (100 ml) and toluene (3×100 ml) were added and distilled to remove residual water from the product. After drying under vacuum, the residue was 159.8 g of a dark brown waxy solid (>theory). The purity was approximately 93% by HPLC analysis.

EXAMPLE 3 Preparation of 3-amino-1-(5-bromopyridin-2-yl)-2-(2,4-difluorophenyl)-1,1-difluoropropan-2-ol (±4b-Br)

4-Br (200 g, 1 eq) was added into methanolic ammonia (8.0 L; 40 vol; ammonia content: 15-20% w/v) in an autoclave at 10-20° C. The reaction mixture was gradually heated to 60-65° C. and at 3-4 kg/cm² under sealed conditions for 10-12 h. The reaction progress was monitored by GC. After completion of the reaction, the reaction mixture was cooled to 20-30° C. and released the pressure gradually. The solvent was distilled under reduced pressure below 50° C. and the crude obtained was azeotroped with methanol (2×600 mL, 6 vol) followed by with isopropanol (600 mL, 2 vol) to afford 203 g (96.98% yield, purity by HPLC: 94.04%) of ±4b-Br.

EXAMPLE 4 Preparation of 3-amino-1-(5-bromopyridin-2-yl)-2-(2,4-difluorophenyl)-1,1-difluoropropan-2-ol (4b-Br or 2c-Br)

Amino alcohol ±4b-Br (150 g, 1 eq) was dissolved in an isopropanol /acetonitrile mixture (1.5L, 8:2 ratio, 10 vol) and Di-p-toluoyl-L-tartaric acid (L-DPTTA) (84.05 g, 0.55 eq) was added into the reactor at 20-30 ° C. The reaction mixture was heated to 45-50° C. for 1 1.5 h (Note: The reaction mixture becomes clear and then became heterogeneous). The reaction mixture was gradually cooled to 20-30° C. and stirred for 16-18 h. The progress of the resolution was monitored by chiral HPLC analysis.

After the completion of the resolution, the reaction mixture was gradually cooled to 20-35° C. The reaction mixture was filtered and the filtered solid was washed with a mixture of acetonitrile and isopropanol (8:2 mixture, 300 mL, 2 vol) and dried to afford 75 g of the L-DPTTA salt (95.37% ee). The L-DPTTA salt obtained was chirally enriched by suspending the salt in isopropanol/acetonitrile (8:2 mixture; 750 mL, 5 vol) at 45-50° C. for 24-48 h. The chiral enhancement was monitored by chiral HPLC; the solution was gradually cooled to 20-25° C., filtered and washed with an isoporpanol/acetonitrile mixture (8:2 mixture; 1 vol). The purification process was repeated and after filtration, the salt resulted in chiral purity greater than 96% ee. The filtered compound was dried under reduced pressure at 35-40° C. to afford 62 g of the enantio-enriched L-DPPTA salt with 97.12% ee as an off-white solid. The enantio-enriched L-DPTTA salt (50 g, 1 eq) was dissolved in methanol (150 mL, 3 vol) at 20-30° C. and a potassium carbonate solution (18.05 g K₂CO₃ in 150 mL water) was slowly added at 20-30° C. under stirring. The reaction mixture was maintained at this temperature for 2-3 h (pH of the solution at was maintained at 9). Water (600 mL, 12 vol) was added into the reaction mixture through an additional funnel and the reaction mixture was stirred for 2-3 h at 20-30° C. The solids were filtered; washed with water (150 mL, 3 vol) and dried under vacuum at 40-45° C. to afford 26.5 g of amino alcohol 4b-Br or 4c-Br with 99.54% chemical purity, 99.28% ee as an off-white solid. (Water content of the chiral amino alcohol is below 0.10% w/w).

¹H NMR: δ values with respect to TMS (DMSO-d₆; 400 MHz):8.68; (1H, d, J=2.0 Hz, Ar—H), 8.16; (1H, dd, J=8.0 Hz, 2.0 Hz, Ar—H), 7.49-7.43; (1H, m, Ar—H), 7.40; (1H, d, J=8 Hz, Ar—H), 7.16-7.11; (1H, m, Ar—H), 7.11-6.99; (1H, m, Ar—H), 3.39-3.36; (1H, m, —OCH_(A)H_(B)—), 3.25-3.22; (1H, m, —OCH_(A)H_(B)—).¹³C NMR:163.87-158.52; (dd, 2 x Ar—C—), 150.88; (Ar—C), 149.16; (Ar—C), 139.21; (Ar—C), 132.39; (Ar—C), 124.49; (Ar—C), 122.17; (Ar—C), 121.87; (d, Ar—C), 119.91; (t, —CF₂—), 110.68; (Ar—C), 103.97; (t, Ar—C), 77.41; (t,-C-OH), 44.17; (—CH₂—NH₂).

EXAMPLE 5 Preparation of 1-(5-bromopyridin-2-yl)-2-(2,4-difluorophenyl)-1,1-difluoro-3-(1H-tetrazol-1-yl)propan-2-ol (1-6*-Br or 1-7*-Br)

4b-Br or 4c-Br (20.0 g, 1 eq.) was added to acetic acid (50 mL, 2.5 vol) at 25-35° C. followed by the addition of anhydrous sodium acetate (4.32 g, 1 eq), trimethyl orthoformate (15.08 g, 2.7 eq). The reaction mixture was stirred for 15-20 min at this temperature and trimethylsilyl azide (12.74 g, 2.1 eq) was added to the reaction mixture (Chilled water was circulated through the condenser to minimize the loss of trimethylsilyl azide from the reaction mixture by evaporation). The reaction mixture was then heated to 70-75° C. and maintained at this temperature for 2-3 h. The reaction progress was monitored by HPLC. Once the reaction was complete, the reaction mixture was cooled to 25-35° C. and water (200 mL, 10 vol) was added. The reaction mixture was extracted with ethyl acetate (400 mL, 20 vol) and the aqueous layer was back extracted with ethyl acetate (100 mL, 5 vol). The combined organic layers were washed with 10% potassium carbonate solution (3×200 mL; 3×10 vol) followed by a 10% NaCl wash (1×200 mL, 10 vol). The organic layer was distilled under reduced pressure below 45° C. The crude obtained was azeotroped with heptanes (3×200 mL) to get 21.5g (94% yield, 99.26 5 purity) of tetrazole 1-6* or 1-7* compound as pale brown solid (low melting solid).

¹H NMR: δ values with respect to TMS (DMSO-d₆; 400 MHz NMR instrument):9.13; (1H, Ar—H), 8.74; (1H, Ar—H), 8.22-8.20; (1H, m, Ar—H), 7.44; (1H, d, J=7.2 Hz, Ar—H), 7.29; (1H Ar—H), 7.23-7.17; (1H, m, Ar—H), 6.92-6.88; (1H, Ar—H), 5.61; (1H, d, J=11.2 Hz, —OCH_(A)H_(B)—), 5.08; (1H, d, J=5.6 Hz, —OCH_(A)H_(B)—).¹³C NMR:163.67-161.59; (dd, Ar—C—), 160.60-158.50; (dd, Ar—C—), 149.65; (Ar—C), 144.99; (Ar—C), 139.75; (Ar—C), 131.65; (Ar—C), 124.26; (Ar—C), 122.32; (d, Ar—C), 119.16; (t, —CF₂—), 118.70; (d, Ar—C), 111.05; (d, Ar—C) 104.29; (t, Ar—C), 76.79; (t,—C—OH), 59.72; (Ar—C), 50.23; (—OCH₂N—).

EXAMPLE 6 Preparation of 2-(2,4-difluorophenyl)-1,1-difluoro-3-(1H-tetrazol-1-yl)-1-(5-(4-(2,2,2-trifluoroethoxy)phenyl)pyridin-2-yl)propan-2-ol (1 or 1a) A. Preparation of 1 or 1a via 1-6*-Br or 1-7*-Br

Synthesis of 4,4,5,5-tetramethyl-2-(4-(2,2,2-trifluoroethoxy)phenyl)-1,3,2-dioxaborolane Potassium carbonate (59.7 g, 2.2 eq.) was added to a slurry of DMF (190 mL, 3.8 Vol.), 4-Bromo phenol (37.4g, 1.1 eq.) and 2,2,2-trifluroethyl tosylate (50.0 g, 1.0 eq.) at 20-35° C. under an inert atmosphere. The reaction mixture was heated to 115-120° C. and maintained at this temperature for 15-18 h. The reaction progress was monitored by GC. The reaction mixture was then cooled to 20-35° C., toluene (200 mL, 4.0 vol.) and water (365 mL, 7. 3 vol.) were added at the same temperature, stirred for 10-15 minutes and separated the layers.

The aqueous layer was extracted with toluene (200 mL, 4.0 vol.). The organic layers were combined and washed with a 2M sodium hydroxide solution (175 mL, 3.5 vol.) followed by a 20% sodium chloride solution (175 mL, 3.5 vol.). The organic layer was then dried over anhydrous sodium sulfate and filtered. The toluene layer was transferred into clean reactor, spurged with argon gas for not less than 1 h. Bis(Pinacolato) diborane (47 g, 1.1 eq.), potassium acetate (49.6 g, 3.0 eq.) and 1,4-dioxane (430 mL, 10 vol.) were added at 20-35° C., and spurged the reaction mixture with argon gas for at least 1 h. Pd(dppf)Cl₂ (6.88 g, 0.05 eq) was added to the reaction mixture and continued the argon spurging for 10-15 minutes. The reaction mixture temperature was increased to 70-75° C., maintained the temperature under argon atmosphere for 15-35 h and monitored the reaction progress by GC. The reaction mixture was cooled to 20-35° C., filtered the reaction mixture through a Celite pad, and washed with ethyl acetate (86 mL, 2 vol.). The filtrate was washed with water (430 mL, 10 vol.). The aqueous layer was extracted with ethyl acetate (258 mL, 6 vol.) and washed the combined organic layers with a 10% sodium chloride solution (215 mL, 5 vol.). The organic layer was dried over anhydrous sodium sulfate (43 g, 1 time w/w), filtered and concentrated under reduced pressure below 45° C. to afford crude 4,4,5,5-tetramethyl-2-(4-(2,2,2-trifluoroethoxy)phenyl)-1,3,2-dioxaborolane (65 g; 71% yield with the purity of 85.18% by GC). The crude 4,4,5,5-tetramethyl-2-(4-(2,2,2-trifluoroethoxy)phenyl)-1,3,2-dioxaborolane (65 g, 1 eq.) was dissolved in 10% ethyl acetate—n-Heptane (455 mL, 7 vol.) and stirred for 30-50 minutes at 20-35° C. The solution was filtered through a Celite bed and washed with 10% ethyl acetate in n-Heptane (195 mL, 3 vol.). The filtrate and washings were pooled together, concentrated under vacuum below 45° C. to afford 4,4,5,5-tetramethyl-2-(4-(2,2,2-trifluoroethoxy)phenyl)-1,3,2-dioxaborolane as a thick syrup (45.5 g; 70% recovery). This was then dissolved in 3% ethyl acetate-n-heptane (4 vol.) and adsorbed on 100-200 M silica gel (2 times), eluted through silica (4 times) using 3% ethyl acetate—n-heptane. The product rich fractions were pooled together and concentrated under vacuum. The column purified fractions (>85% pure) were transferred into a round bottom flask equipped with a distillation set-up. The compound was distilled under high vacuum below 180° C. and collected into multiple fractions. The purity of fractions was analyzed by GC (should be >98% with single max impurity <1.0%). The less pure fractions (>85% and <98% pure fraction) were pooled together and the distillation was repeated to get 19g (32% yield) of 4,4,5,5-tetramethyl-2-(4-(2,2,2-trifluoroethoxy)phenyl)-1,3,2-dioxaborolane as a pale yellow liquid.

¹H NMR: δ values with respect to TMS (DMSO-d⁶; 400 MHz):7.64; (2H, d, 6.8 Hz), 7.06; (2H, d, J=6.4 Hz), 4.79; (2H, q, J=6.8 Hz), 1.28; (12H, s).

¹³C NMR: 159.46; (Ar—C—O—), 136.24; (2 x Ar—C—), 127.77-120.9; (q, —CF₃), 122.0; (Ar—C—B), 114.22; (2 x Ar—C—), 64.75; (q, J=27.5 Hz).

Synthesis of 2-(2,4-difluorophenyl)-1,1-difluoro-3-(1H-tetrazol-1-yl)-1-(5-(4-(2,2,2-trifluoroethoxy)phenyl)pyridin-2-yl)propan-2-ol (1 or 1a)

1-6*-Br or 1-7*-Br (14 g, 0.03 mol, 1 eq) was added to tetrahydrofuran (168 mL, 12 vol) at 25-35° C. and the resulting solution was heated to 40-45° C. The reaction mixture was maintained at this temperature for 20-30 min under argon bubbling. Sodium carbonate (8.59 g, 0.08 mol, 2.5 eq) and water (21 mL, 1.5 vol) were added into the reaction mixture and the bubbling of argon was continued for another 20 30 min. 4,4,5,5-tetramethyl-2-(4-(2,2,2-trifluoroethoxy)phenyl)-1,3,2-dioxaborolane (10.76 g, 1.1 eq) dissolved in tetrahydrofuran (42 mL, 3 vol) was added into the reaction mixture and argon bubbling was continued for 20-30 min. Pd(dppf)Cl₂ (2.65 g, 0.1 eq) was added to the reaction mixture under argon bubbling and stirred for 20-30 min (Reaction mixture turned into dark red color). The reaction mixture was heated to 65-70° C. and maintained at this temperature for 3-4 h. The reaction progress was monitored by HPLC. The reaction mixture was cooled to 40-45° C. and the solvent was distilled under reduced pressure. Toluene (350 mL, 25 vol.) was added to the reaction mixture and stirred for 10-15 min followed by the addition of water (140 mL, 10 vol). The reaction mixture was filtered through Hyflo (42 g, 3 times), the layers were separated and the organic layer was washed with water (70 mL, 5 vol) and a 20% w/w sodium chloride solution (140 mL, 10 vol). The organic layer was treated with charcoal (5.6 g, 0.4 times, neutral chalrcoal), filtered through Hyflo. (1S)-10-Camphor sulfonic acid (7.2 g, 1 eq.) was added to the toluene layer and the resulting mixture was heated to 70-75° C. for 2-3 h. The reaction mixture was gradually cooled to 25-35° C. and stirred for 1-2 h. The solids were filtered, washed with toluene (2×5 vol.) and then dried under vacuum below 45° C. to afford 18.0 g of an off white solid. The solids (13.5 g, 1 eq.) were suspended in toluene (135 mL, 10 vol) and neutralized by adding 1M NaOH solution (1.48 vol, 1.1 eq) at 25-35° C. and stirred for 20-30 min Water (67.5 mL, 5 vol) was added to the reaction mixture and stirred for 10-15 min, and then the layers were separated. The organic layer was washed with water (67.5 mL, 5 vol) to remove the traces of CSA. The toluene was removed under reduced pressure below 45° C. to afford crude 1 or 1a. Traces of toluene were removed by azeotroping with ethanol (3×10 vol), after which light brown solid of crude 1 or 1a (7.5 g, 80% yield) was obtained. The crude 1 or 1a (5 g) was dissolved in ethanol (90 mL, 18 vol.) at 20-35° C., and heated to 40-45° C. Water (14 vol) was added to the solution at 40-45° C., the solution was maintained at this temperature for 30-45 min and then gradually cooled to 20-35° C. The resulting suspension was continued to stir for 16-18 h at 20-35° C., an additional amount of water (4 vol.) was added and the stirring continued for 3-4 h. The solids were filtered to afford 4.0 g (80% recovery) of 1 or 1a (HPLC purity >98%) as an off-white solid.

¹H NMR: δ values with respect to TMS (DMSO-d₆; 400 MHz):9.15; (1H, s, Ar—H), 8.93; (1H, d, J=0.8 Hz, Ar—H), .8.22-8.20; (1H, m, Ar—H), 7.80; (2H, d, J=6.8 Hz, Ar—H), 7.52; (1H, d, J=6.8 Hz, Ar—H), 7.29; (1H, d,J=3.2 Hz, Ar—H), 7.27-7.21; (1H, m, Ar—H), 7.23-7.21; (2H, d, J=6.8 Hz, Ar—H), 7.19; (1H, d, J=6.8 Hz, Ar—H), 6.93-6.89; (1H, m, Ar—H), 5.68; (1H, J=12 Hz, —CH_(A)H_(B)), 5.12; (2H, d, J=11.6 Hz, —CH_(A)H_(B)), 4.85; (2H, q, J=7.6 Hz).

¹³C NMR: 163.93-158.33; (m, 2 x Ar—C), 157.56; (Ar—C), 149.32; (t, Ar—C), 146.40; (Ar—C), 145.02; (Ar—C), 136.20; (Ar-C), 134.26; (2 x Ar—C), 131.88-131.74; (m, AR—C), 129.72; (Ar—C), 128.47; (2 x Ar—C), 123.97; (q, —CF₂—), 122.41; (Ar—C), 119.30; (—CF₃), 118.99; (Ar—C), 115.65; (2 x Ar—C), 110.99; (d, Ar—C), 104.22; (t, Ar—C), 77.41-76.80; (m, Ar—C), 64.72; (q, —OCH₂—CF₃), 50.54; (—CH₂—N—).

B. Preparation of 1 or 1a via 4b-Br or 4c-Br

Synthesis of 3 -amino-2-(2,4-difluorophenyl)-1,1 -difluoro-1-(5 -(4-(2,2,2-trifluoroethoxy)phenyl)pyridin-2-yl)propan-2-ol (8a or 8b) Potassium carbonate (30.4 g) and water (53.3 g) were charged to a 1-L flask equipped with overhead stirring, thermocouple, and nitrogen/vacuum inlet valve, and stirred until dissolved. The boronic acid (19.37 g), a solution of 4b-Br or 4c-Br in 2-butanol (103.5 g, 27.8 g theoretical 4b-Br or 4c-Br)) and 2-BuOH (147.1 g) were added and stirred to form a clear mixture. The flask was evacuated and refilled with nitrogen 3 times. Pd(dppf)₂Cl₂ (0.30 g) was added and stirred to form a light orange solution. The flask was evacuated and refilled with nitrogen 4 times. The mixture was heated to 85° C. and stirred overnight and endpointed by HPLC analysis. The reaction mixture was cooled to 60° C. and the layers were allowed to settle. The aqueous layer was separated. The organic layer was washed with 5% NaCl solution (5×100 ml) at 30-40° C. The organic layer was filtered and transferred to a clean flask with rinses of 2-BuOH. The combined solution was 309.7 g, water content 13.6 wt % by KF analysis. The solution was diluted with 2-BuOH (189 g) and water (10 g). Theoretically the solution contained 34.8 g product, 522 ml (15 volumes) of 2-BuOH, and 52.2 ml (1.5 volumes) of water. L-Tartaric acid (13.25 g) was added and the mixture was heated to a target temperature of 70-75° C. During the heat-up, a thick suspension formed. After about 15 minutes at 70-72° C. the suspension became fluid and easily stirred. The suspension was cooled at a rate of 10° C./hour to 25° C. then stirred at 25° C. for about 10 hours. The product was collected on a vacuum filter and washed with 10:1 (v/v) 2-BuOH/water (50 ml) and 2-butanol (40 ml). The salt was dried in a vacuum oven at 60° C. with a nitrogen purge for 2 days. The yield was 40.08 g of 8a or 8b as a fluffy, grayish-white solid. The water content was 0.13 wt % by KF analysis. The yield was 87.3% with an HPLC purity of 99.48%.

Synthesis of 2-(2,4-difluorophenyl)-1,1-difluoro-3-(1H-tetrazol-1-yl)-1-(5-(4-(2,2,2-trifluoroethoxy)phenyl)pyridin-2-yl)propan-2-ol (1 or 1a)

To a 350 ml pressure bottle were charged acetic acid (73 ml), 8a or 8b (34.8 g), sodium acetate (4.58 g) and trimethylorthoformate (16.0 g). The mixture was stirred for 18 min at room temperature until a uniform suspension was obtained. Azidotrimethylsilane (8.88 g) was added and the bottle was sealed. The bottle was immersed in an oil bath and magnetically stirred. The oil bath was at 52° C. initially, and was warmed to 62-64° C. over about ½ hour. The suspension was stirred at 62-64° C. overnight. After 20.5 hours the suspension was cooled to room temperature and sampled. The reaction was complete by HPLC analysis. The reaction was combined with three other reactions that used the same raw material lots and general procedure (total of 3.0 g additional starting material). The combined reactions were diluted with ethyl acetate (370 ml) and water (368 ml) and stirred for about ½ hour at room temperature. The layers were settled and separated. The organic layer was washed with 10% K₂CO₃ solution (370 ml/397 g) and 20% NaCl solution (370 ml/424 g). The organic layer (319 g) was concentrated, diluted with ethanol (202 g) and filtered, rinsed with ethanol (83 g).

The combined filtrate was concentrated to 74 g of amber solution.

The crude 1 or 1a solution in ethanol (74 g solution, containing theoretically 31.9 g 1 or 1a) was transferred to a 2-L flask equipped with overhead stifling, thermocouple, and addition funnel. Ethanol (335 g) was added including that used to complete the transfer of the 1 or 1a solution. The solution was heated to nominally 50° C. and water (392 g) was added over 12 minutes. The resulting hazy solution was seeded with 1 or 1a crystals and stirred at 50° C. After about 1/2 hour the mixture was allowed to cool to 40° C. over about ½ hour during which time crystallization started. Some darker colored chunky solid separated out from the main suspension. The pH of the crystallizing mixture was adjusted from 4.5 to 6 using 41% KOH (1.7 g). After about 1 hour a good suspension had formed. Additional water (191 g) was added slowly over ½ hour. The suspension was heated to 50° C. and cooled at 5° C./min to room temperature. After stirring overnight the suspension was cooled in a water bath to 16° C. and filtered after 1 hour. The wet cake was washed with 55:45 (v/v) water/ethanol (2×50 ml) and air-dried on the vacuum filter funnel overnight. Further drying at 40° C. in a vacuum oven with a nitrogen bleed resulted in no additional weight loss. The yield was 30.2 g of off-white fine powder plus some darker granular material. By in-process HPLC analysis there was no difference in the chemical purity of the darker and lighter materials. The purity was 99.4%. The water content was 2.16 wt % by KF analysis. The residual ethanol was 1.7 wt % estimated by ¹H NMR analysis. The corrected yield was 29.0 g, 91.0% overall yield for tetrazole formation and crystallization. The melting point was 65° C. by DSC analysis.

Incorporation by Reference

The contents of all references (including literature references, issued patents, published patent applications, and co-pending patent applications) cited throughout this application are hereby expressly incorporated herein in their entireties by reference.

Equivalents

Those skilled in the art will recognize, or be able to ascertain using no more than routine experimentation, many equivalents of the specific embodiments of the invention described herein. Such equivalents are intended with be encompassed by the following claims. 

What is claimed:
 1. A process to prepare a compound of formula IV:

comprising olefination of a compound of formula III:

to provide a compound of formula IV; wherein R is


2. A process to prepare a compound of formula V or Va, or a mixture thereof:

comprising dihydroxylation of a compound of formula IV:

to provide a compound of formula V or Va, or a mixture thereof; wherein R is


3. A process to prepare a compound of formula VI or VIa, or a mixture thereof:

comprising activation of the primary alcohol of a compound of formula V or Va, or a mixture thereof:

to a provide a compound of formula VI or VIa, or a mixture thereof; wherein R is

and each Y is independently —OSO₂-alkyl, —OSO₂-substituted alkyl, —OSO₂-aryl, —OSO₂-substituted aryl, —O(C═O)-alkyl, —O(C═O)-substituted alkyl, —O(C═O)-aryl, —O(C═O)-substituted aryl, or halogen.
 4. A process to prepare a compound of formula VII or VIIa, or a mixture thereof:

comprising ring closure of a compound of formula VI or Via, or a mixture thereof:

to provide a compound of formula VII or VIIa, or a mixture thereof; wherein R is

and each Y is independently —OSO₂-alkyl, —OSO₂-substituted alkyl, —OSO₂-aryl, —OSO₂-substituted aryl, —O(C═O)-alkyl, —O(C═O)-substituted alkyl, —O(C═O)-aryl, —O(C═O)-substituted aryl, or halogen.
 5. A process to prepare compound 1 or 1a, or a mixture thereof:

comprising converting a compound of formula Vb or Vc, or a mixture thereof:

to compound 1 or 1a, or a mixture thereof; wherein each R₂ is independently

halo, —O(C═O)-alkyl, —O(C═O)-substituted alkyl, —O(C═O)-aryl, —O(C═O)-substituted aryl, —O(C═O)—O-alkyl, —O(C═O)—O-substituted alkyl, —O(C═O)-O-aryl, —O(C═O)—O-substituted aryl, —O(SO₂)-alkyl, —O(SO₂)-substituted alkyl, —O(SO₂)-aryl, or —O(SO₂)-substituted aryl.
 6. The process of claim 5, further comprising reacting a compound of formula IVa:

under asymmetric dihydroxylation conditions to provide a compound of formula Vb or Vc, or mixtures thereof:

wherein the asymmetric dihydroxylation conditions comprise: (i) AD-mix alpha or AD-mix beta; or (ii) a first oxidant in catalytic amount, a second oxidant in stoichiometric amount, a base, and a chiral ligand; and wherein each R₂ is independently

halo, —O(C═O)-alkyl, —O(C═O)-substituted alkyl, —O(C═O)-aryl, —O(C═O)-substituted aryl, —O(C═O)—O-alkyl, —O(C═O)—O-substituted alkyl, —O(C═O)—O-aryl, —O(C═O)—O-substituted aryl, —O(SO₂)-alkyl, —O(SO₂)-substituted alkyl, —O(SO₂)-aryl, or —O(SO₂)-substituted aryl.
 7. The process of claim 6, wherein: (i) the first oxidant in catalytic amount is OsO₄ or K₂OsO₂(OH)₄; (ii) the second oxidant in stoichiometric amount is K₃Fe(CN)₆ or N-methylmorpholine-N-oxide; (iii) the base is Cs₂CO₃, Na₂CO₃, K₂CO₃ or NaHCO₃; and (iv) the chiral ligand is selected from the group consisting of (DHQ)₂PHAL, (DHQD)₂PHAL, (DHQD)₂AQN, (DHQ)₂AQN, (DHQD)₂PYR, and (DHQ)₂PYR.
 8. The process of claim 7, wherein the chiral ligand is selected from the group consisting of (DHQ)₂PHAL, (DHQD)₂PHAL, (DHQD)₂AQN, and (DHQD)₂PYR.
 9. The process of claim 6, further comprising the addition of MeSO₂NH₂.
 10. The process of claim 5, further comprising converting a compound of formula VIb or Vic, or a mixture thereof:

to a compound of formula VII or VIIa, or a mixture thereof:

wherein each R₂ is independently

halo, —O(C═O)-alkyl, —O(C═O)-substituted alkyl, —O(C═O)-aryl, —O(C═O)-substituted aryl, —O(C═O)—O-alkyl, —O(C═O)—O-substituted alkyl, —O(C═O)-O-aryl, —O(C═O)—O-substituted aryl, —O(SO₂)-alkyl, —O(SO₂)-substituted alkyl, —O(SO₂)-aryl, or —O(SO₂)-substituted aryl; and each Y is independently —OSO₂-alkyl, —OSO₂-substituted alkyl, —OSO₂-aryl, —OSO₂-substituted aryl, —O(C═O)-alkyl, —O(C═O)-substituted alkyl, —O(C═O)-aryl, —O(C═O)-substituted aryl, or halogen.
 11. The process of claim 6, further comprising: (i) activating the primary alcohol of 2-6a or 2-6c,

or a mixture thereof, to provide a compound of formula 2-7a or 2-7c,

or a mixture thereof; wherein each Y is independently —OSO₂-alkyl, —OSO₂-substituted alkyl, —OSO₂-aryl, —OSO₂-substituted aryl, —O(C═O)-alkyl, —O(C═O)-substituted alkyl, —O(C=O)-aryl, —O(C═O)-substituted aryl, or halogen; (ii) ring-closing of a compound of 2-7a or 2-7c,

or a mixture thereof, to provide epoxide 5* or 5b*,

or a mixture thereof; (iii) ring-opening 5* or 5b*,

or a mixture thereof, to provide amino-alcohol 1-6* or 1-7*,

or a mixture thereof; and (iv) forming the terazole of amino-alcohol 1-6* or 1-7*,

to provide compound 1 or 1a,

or a mixture thereof.
 12. The process of claim 11, wherein Y is mesylate or tosylate.
 13. The process of claim 6, further comprising: (i) activating the primary alcohol 2-6b or 2-6d,

or a mixture thereof, to provide a compound of formula 2-7b or 2-7d,

or a mixture thereof; wherein each Y is independently —OSO₂-alkyl, —OSO₂-substituted alkyl, —OSO₂-aryl, —OSO₂-substituted aryl, —O(C═O)-alkyl, —O(C═O)-substituted alkyl, —O(C═O)-aryl, —O(C═O)-substituted aryl, or halogen; (ii) ring-closing of compound 2-7b or 2-7d,

or a mixture thereof, to provide epoxide 4* or 4c*,

or a mixture thereof; (iii) ring-opening epoxide 4* or 4c*,

or a mixture thereof, to provide amino-alcohol 4b or 4c,

or a mixture thereof; (iv) arylating amino-alcohol 4b or 4c,

or a mixture thereof, to provide aryl-pyridine 1-6* or 1-7*,

or a mixture thereof; and (v) forming the tetrazole of amino-alcohol 1-6* or 1-7*,

or a mixture thereof, to provide compound 1 or 1a,

or a mixture thereof; wherein each R₁ is independently halo, —O(C═O)-alkyl, —O(C═O)-substituted alkyl, —O(C═O)-aryl, —O(C═O)-substituted aryl, —O(C═O)—O-alkyl, —O(C═O)—O-substituted alkyl, —O(C═O)—O-aryl, —O(C═O)—O-substituted aryl, —O(SO₂)-alkyl, —O(SO₂)-substituted alkyl, —O(SO₂)-aryl, or —O(SO₂)-substituted aryl.
 14. A compound of formula IVb:

wherein R is

and each R₁₂ is independently H, optionally substituted alkyl, optionally substituted alkenyl, optionally substituted aryl, optionally substituted heteroaryl, optionally substituted cycloalkyl, or optionally substituted hetrocyclyl.
 15. A compound of formula VI* or VIa*, or a mixture thereof:

wherein R is

and each Y₁ is independently OH, —OSO₂-alkyl, —OSO₂-substituted alkyl, —OSO₂-aryl, —OSO₂-substituted aryl, —O(C═O)-alkyl, —O(C═O)-substituted alkyl, —O(C═O)-aryl, —O(C═O)-substituted aryl, or halogen; and each R₁₂ is independently H, optionally substituted alkyl, optionally substituted alkenyl, optionally substituted aryl, optionally substituted heteroaryl, optionally substituted cycloalkyl, or optionally substituted hetrocyclyl.
 16. The process of any one of claim 11 or 13, further comprising: (i) combining compound 1 or 1a,

or a mixture thereof, a sulfonic acid

and a crystallization solvent or crystallization solvent mixture; (ii) diluting the mixture from step (i) with a crystallization co-solvent or crystallization co-solvent mixture; and (iii) isolating a compound of formula IX or IXa.

or a mixture thereof; wherein each Z is independently aryl, substituted aryl, alkyl, or substituted alkyl.
 17. The process of claim 16, wherein Z is phenyl, p-tolyl, methyl, or ethyl.
 18. The process of claim 16, wherein the crystallization solvent or crystallization solvent mixture is ethyl acetate, isopropyl acetate, ethanol, methanol, or acetonitrile, or combinations thereof.
 19. The process of claim 16, wherein the crystallization co-solvent or crystallization co-solvent mixture is pentane, methyl tert-butylether, hexane, heptane, or toluene, or combinations thereof.
 20. A process to prepare a compound of formula 5* or 5b*,

or a mixture thereof, the method comprising converting a compound of formula IVa,

wherein each R₂ is independently

halo, —O(C═O)-alkyl, —O(C═O)-substituted alkyl, —O(C═O)-aryl, —O(C═O)-substituted aryl, —O(C═O)—O-alkyl, —O(C═O)—O-substituted alkyl, —O(C═O)—O-aryl, —O(C═O)—O-substituted aryl, —O(SO₂)-alkyl, —O(SO₂)-substituted alkyl, —O(SO₂)-aryl, or —O(SO₂)-substituted aryl.
 21. The process of claim 20 further comprising reacting a compound of formula IVa:

under asymmetric dihydroxylation conditions to provide a compound of formula Vb or Vc, or mixtures thereof:

wherein the asymmetric dihydroxylation conditions comprise: (i) AD-mix alpha or AD-mix beta; or (ii) a first oxidant in catalytic amount, a second oxidant in stoichiometric amount, a base, and a chiral ligand; and wherein each R₂ is independently

halo, —O(C═O)-alkyl, —O(C═O)-substituted alkyl, —O(C═O)-aryl, —O(C═O)-substituted aryl, —O(C═O)—O-alkyl, —O(C═O)—O-substituted alkyl, —O(C═O)—O-aryl, —O(C═O)—O-substituted aryl, —O(SO₂)-alkyl, —O(SO₂)-substituted alkyl, —O(SO₂)-aryl, or —O(SO₂)-substituted aryl.
 22. The process of claim 20 further comprising converting a compound of formula Vb or Vc, or a mixture thereof:

to provide a compound of formula of 5* or 5b*,

or a mixture thereof;

wherein each R₂ is independently halo, —O(C═O)-alkyl, —O(C═O)-substituted alkyl, —O(C═O)-aryl, —O(C═O)-substituted aryl, —O(C═O)—O-alkyl, —O(C═O)—O-substituted alkyl, —O(C═O)—O-aryl, —O(C═O)—O-substituted aryl, —O(SO₂)-alkyl, —O(SO₂)-substituted alkyl, —O(SO₂)-aryl, or —O(SO₂)-substituted aryl.
 23. The process of claim 20 further comprising: (i) arylating a compound of formula IVa,

to afford a compound of formula IV,

(ii) dihydroxylating IV,

to afford a compound of formula V or Va,

or a mixture thereof; (iii) activating the primary alcohol of a compound of formula V or Va,

or a mixture thereof, to provide a compound of formula 2-7a or 2-7c,

or a mixture thereof; and (iv) ring-closing of a compound of formula 2-7a or 2-7c,

or a mixture thereof, to afford a compound of formula of 5* or 5b*,

or a mixture thereof; wherein R is

each R₂ is independently

halo, —O(C═O)-alkyl, —O(C═O)-substituted alkyl, —O(C═O)-aryl, —O(C═O)-substituted aryl, —O(C═O)—O-alkyl, —O(C═O)—O-substituted alkyl, —O(C═O)—O-aryl, —O(C═O)—O-substituted aryl, —O(SO₂)-alkyl, —O(SO₂)-substituted alkyl, —O(SO₂)-aryl, or —O(SO₂)-substituted aryl; and each Y is independently —OSO₂-alkyl, —OSO₂-substituted alkyl, —OSO₂-aryl, —OSO₂-substituted aryl, —O(C=O)-alkyl, —O(C═O)-substituted alkyl, —O(C═O)-aryl, —O(C═O)-substituted aryl, or halogen.
 24. The process of claim 20 further comprising: (i) dihydroxylating a compound of formula IVa,

to afford a compound of formula Vb or Vc,

or a mixture thereof; (ii) arylating a compound of formula Vb or Vc,

or a mixture thereof, to afford a compound of formula V or Va,

or a mixture thereof; (iii) activating the primary alcohol of a compound of formula V or Va,

or a mixture thereof, to provide a compound of formula 2-7a or 2-7c,

or a mixture thereof; and (iv) ring-closing of a compound of formula 2-7a or 2-7c,

or a mixture thereof, to afford a compound of formula of 5* or 5b*,

or a mixture thereof; wherein R is

each R₂ is independently

halo, —O(C═O)-alkyl, —O(C═O)-substituted alkyl, —O(C═O)-aryl, —O(C═O)-substituted aryl, —O(C═O)—O-alkyl, —O(C═O)—O-substituted alkyl, —O(C═O)—O-aryl, —O(C═O)—O-substituted aryl, —O(SO₂)-alkyl, —O(SO₂)-substituted alkyl, —O(SO₂)-aryl, or —O(SO₂)-substituted aryl; and each Y is independently —OSO₂-alkyl, —OSO₂-substituted alkyl, —OSO₂-aryl, —OSO₂-substituted aryl, —O(C═O)-alkyl, —O(C═O)-substituted alkyl, —O(C═O)-aryl, —O(C═O)-substituted aryl, or halogen.
 25. The process of claim 20 further comprising: (i) dihydroxylating a compound of formula IVa,

to afford a compound of formula Vb or Vc,

or a mixture thereof; (ii) activating the primary alcohol of a compound of formula Vb or Vc,

or a mixture thereof, to afford a compound of formula VIb or VIc,

or a mixture thereof; (iii) ring-closing of a compound of formula VIb or VIc,

or a mixture thereof, to provide a compound of formula VII or VIIa,

or a mixture thereof; and (iv) arylating a compound of formula VII or VIIa,

or a mixture thereof, to afford a compound of formula 5* or 5b*,

or a mixture thereof; wherein R₂ is independently

halo, —O(C═O)-alkyl, —O(C═O)-substituted alkyl, —O(C═O)-aryl, —O(C═O)-substituted aryl, —O(C═O)—O-alkyl, —O(C═O)—O-substituted alkyl, —O(C═O)—O-aryl, —O(C═O)—O-substituted aryl, —O(SO₂)-alkyl, —O(SO₂)-substituted alkyl, —O(SO₂)-aryl, or —O(SO₂)-substituted aryl; and each Y is independently —OSO₂-alkyl, —OSO₂-substituted alkyl, —OSO₂-aryl, —OSO₂-substituted aryl, —O(C═O)-alkyl, —O(C═O)-substituted alkyl, —O(C═O)-aryl, —O(C═O)-substituted aryl, or halogen.
 26. The process of any one of claims 20-25 further comprising: (i) ring opening of a compound of formula VII or VIIa,

or a mixture thereof, to afford 1-6* or 1-7*,

or a mixture thereof; wherein each R₂ is independently

halo, —O(C═O)-alkyl, —O(C═O)-substituted alkyl, —O(C═O)-aryl, —O(C═O)-substituted aryl, —O(C═O)—O-alkyl, —O(C═O)—O-substituted alkyl, —O(C═O)—O-aryl, —O(C═O)—O-substituted aryl, —O(SO₂)-alkyl, —O(SO₂)-substituted alkyl, —O(SO₂)-aryl, or —O(SO₂)-substituted aryl.
 27. The process of claim 26, further comprising: (i) forming the tetrazole of 1-6* or 1-7*,

or a mixture thereof to afford compound 1 or 1a, or a mixture thereof: 